Weak covalent crosslinks in thermosets for toughness

Abstract

The present disclosure provides a polymer material comprising weak cross-linked covalent bonds and / or weak cross-linked units comprising weak covalent bonds. Weak covalent bonds can be used to replace the hydrogen bonds present in traditional polymer materials (e.g., polyurethanes). Advantageously, toughness can be controlled by changing the strength of the weak covalent bonds and / or by changing the number of weak covalent cross-links. Cross-linked materials using weak covalent cross-links can be used to manufacture tough materials that can resist stress relaxation. In addition, the present disclosure provides polymer chains and polymer materials comprising intrachain rings (also referred to herein as rings). The intrachain rings comprise weak bonds and / or comprise weak bridges of at least one weak bond. The present disclosure also provides compositions comprising polymer chains, materials comprising polymer chains, monomeric units that can react to form polymer chains comprising intrachain rings, resins comprising monomeric units, and related materials, devices, and uses.

Description

[0001] Cross-references

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 989,307, filed on March 13, 2020, and U.S. Provisional Patent Application No. 62 / 989,314, filed on March 13, 2020, the entire contents of each of which are incorporated herein by reference. Background Art

[0003] Polyurethanes have been incorporated into many devices and materials. Tough polyurethanes have high levels of hydrogen bonding, a type of weak, dynamic bond that contributes to the material's toughness. These weak hydrogen bonds accumulate along the polyurethane chain and contribute to the material's toughness.

[0004] The presence of weak hydrogen bonds in polyurethanes makes the material susceptible to performance degradation in the presence of water. Materials with high levels of hydrogen bonding readily absorb water, which can act as a plasticizer in the polymer network, reducing the polymer's ability to resist long-term creep or stress. Water also reduces the toughness of polymer materials due to its effect on dynamic hydrogen bonds, making them more dynamic and weaker. Tough polymer materials exposed to aqueous environments (e.g., polyurethane orthodontic appliances exposed to the mouth) may experience disruption of these hydrogen bonds by water. Summary of the Invention

[0005] Provided herein are polymeric materials comprising weakly covalently crosslinked units. Such polymeric materials can increase the toughness of a material without being significantly affected by the presence of water and can be used for applications including the direct manufacture of devices (e.g., orthodontic devices). Also provided herein are objects manufactured using the polymeric materials, resins for forming the polymeric materials, objects made therefrom, and methods for forming and using the polymeric materials.

[0006] In various aspects, the present disclosure provides a polymer material comprising a first polymer chain; a second polymer chain; and a weak cross-linking unit, which is attached to the first polymer chain at the first end of the weak cross-linking unit and attached to the second polymer chain at the second end of the weak cross-linking unit, wherein the weak cross-linking unit includes a weak cross-linking bond between the first end and the second end, wherein the weak cross-linking bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some aspects, the weak cross-linking unit is a weak cross-linking bond. In some aspects, the polymer material comprises a plurality of weak cross-linking units. In some aspects, the plurality of weak cross-linking units are attached to the first polymer chain at the first end and to the second polymer chain at the second end.

[0007] In various aspects, the present disclosure provides a polymeric material comprising a first polymer chain; a second polymer chain; and a weak crosslink attached to the first polymer chain at a first end and to the second polymer chain at a second end, wherein the weak crosslink has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some aspects, the polymeric material comprises a plurality of weak crosslinks. In some aspects, the plurality of weak crosslinks are attached to the first polymer chain at a first end and to the second polymer chain at a second end.

[0008] In various aspects, the present disclosure provides a polymer material comprising: a first polymer chain; a second polymer chain; and an activatable unit attached to the first polymer chain at a first end and to the second polymer chain at a second end, wherein the activatable unit is converted into a weak cross-linking unit when activated by a catalyst, the weak cross-linking unit being attached to the first polymer chain at a first end and to the second polymer chain at a second end, the weak cross-linking unit comprising a weak cross-linking bond between the first end and the second end, the weak cross-linking bond having a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some aspects, the weak cross-linking unit is a weak cross-linking bond. In some aspects, the polymer material further comprises a catalyst.

[0009] In some aspects, the bond dissociation energy of the weak cross-links is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In some aspects, the first polymer chain, the second polymer chain, or each of the first and second polymer chains comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links. In certain aspects, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the first polymer chain, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In some aspects, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the first polymer chain, wherein the ratio is from 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:10 ... :5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500. In some aspects, the polymeric material comprises a ratio of the longest length of the weakly cross-linked units to the longest length of the second polymer chain, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, or less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500.In some aspects, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the second polymer chain, wherein the ratio is 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:100 to 1:200, 1:100 to 1:200, 1:200 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:100 to 1:200, 1:2 ... :5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500.

[0010] In some aspects, the polymeric material further comprises a strong cross-linking unit, wherein the strong cross-linking unit is attached to the first polymer chain at the first end, the strong cross-linking unit is attached to the second polymer chain at the second end, and the strong cross-linking unit comprises one or more bonds forming a chain connected to the first end and the second end, each of the one or more bonds having a bond dissociation energy greater than or equal to 275 kJ / mol. In some aspects, the polymeric material comprises a ratio of the number of weak cross-linking units to the number of strong cross-linking units, wherein the ratio is 1:50 to 5:1, 1:40 to 2:1, 1:30 to 1:1, 1:25 to 1:1, 1:20 to 1:1, 1:15 to 1:1, 1:10 to 1:1, 1:5 to 1:1, 1:30 to 1:5, 1:25 to 1:5, 1:20 to 1:5, 1:20 to 1:10, or 1:10 to 1:5. In some aspects, the ratio is 1:20 to 1:5. In some aspects, the polymeric material includes 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of weakly crosslinked units. In some aspects, the polymeric material includes a ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chains, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10. In certain aspects, the ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chains is 1:1000 to 1:100, 1:900 to 1:150, 1:800 to 1:200, or 1:750 to 1:250.

[0011] In some aspects, the polymeric material comprises a ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the second polymer chains, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10. In some aspects, the ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chain is 1:1000 to 1:100, 1:900 to 1:150, 1:800 to 1:200, or 1:750 to 1:250. In certain aspects, the weak crosslinks are dynamic covalent bonds.

[0012] In some aspects, the weak cross-linking bond is selected from sulfur-sulfur bonds, oxygen-oxygen bonds, nitrogen-nitrogen bonds, silicon-sulfur bonds, silicon-silicon bonds, phosphorus-phosphorus bonds, oxygen-sulfur bonds, nitrogen-phosphorus bonds, carbon-phosphorus bonds, phosphorus-silicon bonds, carbon-sulfur bonds, nitrogen-oxygen bonds and combinations thereof. In some aspects, the weak cross-linking bond is a non-polar covalent bond or a polar covalent bond. In some aspects, the polymeric material includes less than 10wt%, less than 9wt%, less than 8wt%, less than 7wt%, less than 6wt%, less than 5wt%, less than 4wt%, less than 3wt%, less than 2wt% or less than 1wt% hydrogen bonding units. In some aspects, the bond dissociation energy of the weak cross-linking bond is measured as bond dissociation energy or bond breaking energy.

[0013] In some aspects, the polymeric material is hydrophobic. In some aspects, the polymeric material contains less than 10 wt%, less than 5 wt%, less than 1 wt%, or less than 0.5 wt% water after being placed in an aqueous environment at 37° C. for 24 hours. In some aspects, the polymeric material includes a plurality of first polymer chains having an average first polymer chain length, and a plurality of weak crosslinking units having an average weak crosslinking unit length, wherein the average weak crosslinking unit length is less than the first polymer chain average length. In some aspects, the polymeric material has a ratio of an average chain length of weakly crosslinked units to an average chain length of first polymer chains, and wherein the ratio is 1:1.1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:100 to 1:200, In some aspects, the polymeric material comprises a plurality of second polymer chains having a second average polymer chain length; and a plurality of weak crosslinking units having an average weak crosslinking unit chain length, wherein the average weak crosslinking unit chain length is less than or equal to 1:1.1, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500.

[0014] In some respects, each in the first polymer chain, the second polymer chain or the first polymer chain and the second polymer chain comprises a plurality of monomers, each monomer is connected by a main chain covalent bond, and the bond dissociation energy of this main chain covalent bond is higher than the bond dissociation energy of weak cross-linking bond by at least 20kJ / mol, at least 30kJ / mol, at least 40kJ / mol, at least 50kJ / mol, at least 60kJ / mol, at least 70kJ / mol, at least 80kJ / mol, at least 90kJ / mol, at least 100kJ / mol, at least 125kJ / mol, at least 150kJ / mol, at least 175kJ / mol or at least 200kJ / mol. In some respects, the first polymer chain is attached to weak cross-linking unit by covalent bond. In some aspects, the second polymer chain is attached to weak cross-linking unit by covalent bond. In some aspects, at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 20%, at least 30%, at least 40%, or at least 50% of the weak crosslinks are dynamic covalent bonds. In some aspects, the weak crosslinks have a strength of less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond in the polyethylene. In some aspects, the polymeric material comprises a number ratio of the number of weak cross-link units to the number of strong cross-link units, wherein the number ratio is greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, or greater than or equal to 50:1.

[0015] In some aspects, the polymeric material comprises a ratio of the number of weak crosslink units to strong crosslink units, wherein the ratio is 1:100 to 1:1, 1:50 to 1:1, 1:20 to 1:1, 1:10 to 1:1, 1:50 to 50:1, 1:40 to 40:1, 1:30 to 30:1, 1:20 to 20:1, 1:10 to 10:1, 1:1 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:1, 1:10 to 1:100, 1:50 to 1:100, 1:20 to 1:1 :100, 1:50 to 1:100, greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, greater than or equal to 50:1, or greater than or equal to 1:100.

[0016] In some aspects, the polymeric material is characterized by one or more of the following: a tensile modulus greater than or equal to 100 MPa after 24 hours in an aqueous environment at 37°C; a tensile strength at yield greater than or equal to 5 MPa after 24 hours in an aqueous environment at 37°C; a storage modulus greater than or equal to 300 MPa after 24 hours in an aqueous environment at 37°C; a residual flexural stress greater than or equal to 1.5 MPa after 24 hours in an aqueous environment at 37°C; a hardness of 60 Shore A to 85 Shore D after 24 hours in an aqueous environment at 37°C; and an elongation at break greater than or equal to 15% after 24 hours in an aqueous environment at 37°C. In some aspects, the polymeric material is characterized by a residual flexural stress greater than 5% when tested in a humid environment at 37°C for 24 hours. In some aspects, the polymeric material is characterized by a residual stress of 5% to 45% of the initial load, or a residual stress of 20% to 45% of the initial load, after testing in a humid environment at 37°C for 24 hours. In some aspects, the polymeric material is characterized by a tensile modulus of 100 MPa to 3000 MPa, 100 MPa to 2500 MPa, 100 MPa to 2000 MPa, 500 MPa to 3000 MPa, 500 MPa to 2500 MPa, 500 MPa to 2000 MPa, 750 MPa to 3000 MPa, 750 MPa to 2500 MPa, or 750 MPa to 2000 MPa after testing in a humid environment for 24 hours at 37° C. In some aspects, the polymeric material is characterized by an elongation at break greater than 10%, an elongation at break greater than 20%, an elongation at break greater than 30%, an elongation at break of 5% to 250%, an elongation at break of 20% to 250%, or an elongation at break value of 40% to 250%, after testing in a humid environment for 24 hours at 37° C. In some aspects, the polymeric material is characterized by a storage modulus of 0.1 MPa to 4000 MPa, a storage modulus of 300 MPa to 3000 MPa, or a storage modulus of 750 MPa to 3000 MPa after testing in a humid environment at 37°C for 24 hours. In some aspects, the polymeric material is characterized by a residual stress of 0.01 MPa to 15 MPa, or a residual stress of 2 MPa to 15 MPa after testing in a humid environment at 37°C for 24 hours. In some aspects, greater than 70% of visible light passes through the polymeric material. In some aspects, the polymeric material is biocompatible, bioinert, or a combination thereof.

[0017] In some aspects, the polymeric material has a ratio of an average chain length of weakly crosslinked units to an average chain length of a second polymer chain, and wherein the ratio is from 1:1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:100 to 1:100. In some aspects, the second polymer chain average length is greater than the average chain length of the weak crosslink units.

[0018] In various aspects, the present disclosure provides an orthodontic appliance comprising a polymeric material disclosed herein. In some aspects, the orthodontic appliance is an aligner, an expander, or a spacer. In some aspects, the orthodontic appliance includes a plurality of tooth receiving cavities configured to reposition teeth from a first configuration toward a second configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration according to a treatment plan. In some aspects, the orthodontic appliance is an aligner.

[0019] In various aspects, the present disclosure provides a printable resin comprising: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 20 kDa; a weak crosslinking unit comprising a first end and a second end, the weak crosslinking unit comprising a weak crosslink bond located between the first end and the second end; and an initiator, wherein the weak crosslink bond has a weak bond dissociation energy of 50 kJ / mol to 325 kJ / mol.

[0020] In various aspects, the present disclosure provides a printable resin comprising: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 20 kDa; an activatable unit; and an initiator, wherein the activatable unit is converted into a weak crosslinking unit when activated by a catalyst and comprises a weak crosslink between a first end of the weak crosslinking unit and a second end of the weak crosslinking unit, the weak crosslink having a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some aspects, the printable resin further comprises a catalyst.

[0021] In various aspects, the present disclosure provides a printable resin comprising: a plurality of monomers, the plurality of monomers comprising: a first monomer comprising a first weak bond forming unit; and a second monomer comprising a second weak bond forming unit; and an initiator, wherein: the first weak bond forming unit and the second weak bond forming unit combine to form a weak cross-linking unit comprising a first end and a second end, and a weak cross-linking bond located between the first monomer and the second monomer; the weak cross-linking bond has a weak bond dissociation energy of 50 kJ / mol to 325 kJ / mol; and optionally wherein at least some of the plurality of monomers are contained in oligomers having an average chain length of 1 kDa to 20 kDa.

[0022] In some aspects, the weak crosslinking unit is a weak crosslink. In some aspects, the printable resin includes an oligomer with an average chain length of 1 kDa to 20 kDa, wherein the oligomer includes at least some of a plurality of monomers. In some aspects, the printable resin includes a plurality of unreacted monomers and at least one oligomer with a chain length of 1 kDa to 20 kDa. In some aspects, the initiator is a photoinitiator, a thermal initiator, or a combination thereof. In some aspects, the first end of the weak crosslinking unit includes a first reactive functional group. In some aspects, the first reactive functional group is selected from acrylates, methacrylates, thiols, epoxides, allyl ethers, hydroxyls, amines, derivatives thereof, and combinations thereof. In some aspects, the second end of the weak crosslinking unit includes a second reactive functional group. In some aspects, the second reactive functional group is selected from acrylates, methacrylates, thiols, epoxides, allyl ethers, hydroxyls, amines, derivatives thereof, and combinations thereof. In some aspects, the first reactive functional group and the second reactive group are the same. In some aspects, the first terminal reactive functional group and the second terminal reactive group are different functional groups.

[0023] In some aspects, the bond dissociation energy of the weak crosslinks is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In some aspects, the weak crosslinks have a strength of less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond strength in polyethylene. In some aspects, the oligomer comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links. In some aspects, the printable resin comprises a ratio of the longest length of the weakly crosslinked unit to the longest length of the oligomer, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In some aspects, the printable resin comprises a ratio of the longest length of the weakly crosslinked unit to the longest length of the oligomer, wherein the ratio is 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:100 to 1:200, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500.

[0024] In some aspects, the printable resin further comprises a strong cross-linking unit, wherein the strong cross-linking unit comprises a first end and a second end, and the strong cross-linking unit comprises one or more bonds forming a chain connected to the first end and the second end, each of the one or more bonds having a bond dissociation energy greater than or equal to 300 kJ / mol. In some aspects, the plurality of monomers further comprises: a third monomer comprising a first strong bond-forming unit; and a fourth monomer comprising a second strong bond-forming unit, wherein the first strong bond-forming unit and the second strong bond-forming unit combine to form a strong cross-linking unit located between the third monomer and the fourth monomer, the strong cross-linking unit comprising one or more bonds, and each of the one or more bonds has a bond dissociation energy greater than or equal to 300 kJ / mol. In some aspects, the first end of the strong cross-linking unit comprises a first end reactive functional group, the second end of the strong cross-linking unit comprises a second end reactive group, or a combination thereof.

[0025] In some aspects, the printable resin comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 1 wt%, less than 0.5 wt%, or less than 0.1 wt% of weak crosslinking units. In some aspects, the weak crosslinking bonds are selected from sulfur-sulfur bonds, oxygen-oxygen bonds, nitrogen-nitrogen bonds, silicon-sulfur bonds, silicon-silicon bonds, phosphorus-phosphorus bonds, oxygen-sulfur bonds, nitrogen-phosphorus bonds, carbon-phosphorus bonds, phosphorus-silicon bonds, carbon-sulfur bonds, nitrogen-oxygen bonds, and combinations thereof. In some aspects, the weak crosslinking bonds are non-polar covalent bonds or polar covalent bonds. In some aspects, the printable resin comprises less than 10 wt% of hydrogen bonding units. In some aspects, the bond dissociation energy of the weak crosslinking bonds is measured as bond dissociation energy or bond breaking energy.

[0026] In some aspects, the printable resin further comprises a plurality of oligomers having an average oligomer chain length; and a plurality of weak crosslinking units having an average weak crosslinking unit chain length, wherein the average weak crosslinking unit chain length is less than the average oligomer chain length. In some aspects, the resin has a ratio of the average weak crosslinking unit chain length to the average oligomer chain length, and wherein the ratio is 1:1.1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:100 to 1:200. 00, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500.

[0027] In some aspects, the oligomer comprises a plurality of monomers, each of which is covalently linked to a backbone having a bond dissociation energy greater than or equal to 300 kJ / mol. In some aspects, the printable resin further comprises a reactive diluent, a crosslinking modifier, a light blocker, a solvent, a glass transition temperature modifier, a thermal initiator, or a combination thereof. In some aspects, the printable resin further comprises at least one of a polymerization catalyst, an inhibitor, a plasticizer, a surface energy modifier, a pigment, a dye, a filler, a seed crystal, a crystallization catalyst, a bioagent, a catalyst for selective bond breaking, or any combination thereof.

[0028] In some respects, the weak crosslinking unit comprises a polymerizable group. In some respects, the polymerizable group is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, its derivative and combination thereof. In some respects, the oligomer comprises a polymerizable group. In some respects, the polymerizable group of the oligomer is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, its derivative and combination thereof.

[0029] In some aspects, the printable resin has a viscosity of 0.5 PaS to 20 PaS at a printable temperature. In some aspects, the printable temperature is 70° C. to 110° C. In some aspects, the printable temperature is 90° C. In some aspects, the resin is capable of being 3D printed.

[0030] In various aspects, the present disclosure provides a polymer material, comprising: providing a resin disclosed herein; and curing the resin with a light source, thereby forming the polymer material. In some aspects, the method further comprises providing a catalyst for forming weak crosslinks. In some aspects, the polymer material is a polymer material disclosed herein. In some aspects, the method further comprises fabricating an object using the polymer material.

[0031] In some aspects, manufacturing comprises printing using a 3D printer. In some aspects, manufacturing comprises thermal lithography. In some aspects, manufacturing comprises digital light projection. In some aspects, the object is an orthodontic appliance. In some aspects, the orthodontic appliance is an aligner, expander, or spacer. In some aspects, the orthodontic appliance comprises a plurality of tooth sockets configured to reposition teeth from a first configuration toward a second configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration according to a treatment plan. In some aspects, the object is an orthodontic appliance as disclosed herein. In some aspects, the object is an aligner.

[0032] In various aspects, the present disclosure provides a polymeric material produced by the methods described herein. In some aspects, the stress applied to the polymeric material breaks weak crosslinks before breaking covalent bonds of the first polymer chain or the second polymer chain.

[0033] In various aspects, the present disclosure provides a method of repositioning a patient's teeth, the method comprising: applying an orthodontic appliance as described herein to at least one of the patient's teeth; and moving at least one of the patient's teeth toward an intermediate or final tooth arrangement.

[0034] In various aspects, the present disclosure provides a method for repositioning a patient's teeth, the method comprising: generating a treatment plan for the patient, the plan comprising a plurality of intermediate tooth arrangements for moving the teeth from an initial arrangement to a final arrangement along a treatment path; producing a 3D-printed orthodontic appliance comprising a plurality of weakly cross-linked units, wherein the weakly cross-linked units comprise weak cross-linked bonds; and using the orthodontic appliance to move at least one tooth of the patient toward an intermediate arrangement or a final tooth arrangement along the path, wherein the weakly cross-linked bonds have a bond dissociation energy of 50 kJ / mol to 325 kJ / mol.

[0035] In some aspects, the method further comprises tracking the progress of the patient's teeth along the treatment path after applying the orthodontic appliance, the tracking comprising comparing the current arrangement of the patient's teeth with the planned arrangement of the teeth. In some aspects, after 2 weeks of treatment, greater than 60% of the patient's teeth comply with the treatment plan. In some aspects, the orthodontic appliance has a retained repositioning force on at least one of the patient's teeth of at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 70% of the repositioning force initially provided to at least one of the patient's teeth after 2 days. In some aspects, the method further comprises enabling at least one of the patient's teeth to move to an intermediate arrangement or a final tooth arrangement along the path. In some aspects, production comprises direct manufacturing, and optionally, wherein direct manufacturing comprises cross-linking the printable resin disclosed herein. In some aspects, the 3D printed orthodontic appliance is the orthodontic appliance described herein.

[0036] Provided herein are polymeric materials comprising rings comprising weak bonds. Such polymeric materials can have a controllable elongation to tensile strain without damaging the polymer backbone, increasing the retention of stress relaxation. Such polymeric materials can also increase the toughness of materials without being significantly affected by the presence of water, and have applications including directly manufacturing devices (e.g., orthodontic devices). Also provided herein are polymer chains comprising rings, objects manufactured using polymeric materials and / or chains, resins for forming polymeric materials and / or chains and objects made therefrom, and methods for forming and using polymeric materials and / or chains.

[0037] In various aspects, the present disclosure provides a composition comprising: a polymer chain comprising: a ring comprising three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol.

[0038] In various aspects, the present disclosure provides a composition comprising: a polymer chain comprising: a ring comprising three or more ring members; a first bond located between a first set of two ring members, wherein upon catalyst activation, the first bond is convertible into a bond having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol.

[0039] In some respects, the first key has the bond dissociation energy of 50kJ / mol to 325kJ / mol.In some respects, ring comprises a plurality of keys between the group of two ring members, and in described a plurality of keys, the bond dissociation energy of each key is higher than the bond dissociation energy of the first key by at least 20kJ / mol, at least 30kJ / mol, at least 40kJ / mol, at least 50kJ / mol, at least 60kJ / mol, at least 70kJ / mol, at least 80kJ / mol, at least 90kJ / mol, at least 100kJ / mol, at least 125kJ / mol, at least 150kJ / mol, at least 175kJ / mol or at least 200kJ / mol.In some respects, ring comprises substituted or unsubstituted cycloalkane, substituted or unsubstituted heterocycle, substituted or unsubstituted inorganic ring, its derivative or its combination.In some respects, the first key is covalent bond, dihydrogen bond, a plurality of hydrogen bonds, ionic bridge or its combination. In various aspects, the ring includes a weak bridge comprising a first bond.

[0040] In some aspects, the polymer chain comprises a first portion and a second portion, the first portion of the polymer chain is attached to the ring at a first joint, and the second portion of the polymer chain is attached to the ring at a second joint. In some aspects, the first bond is located between the first joint and the second joint, and wherein the second bond is located between the first joint and the second joint.

[0041] In some aspects, the bond dissociation energy of the first bond is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In certain aspects, the polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the first bond.

[0042] In some aspects, the polymer chain comprises a plurality of rings, each ring of the plurality of rings comprising: three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol. In some aspects, the polymer chain comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of rings. In certain aspects, the polymer chain comprises a ratio of the total number of bonds of the ring to the total number of bonds of the polymer chain, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10.

[0043] In some aspects, the ring comprises 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more than 20 ring members. In certain aspects, the ring comprises greater than 10, greater than 15, greater than 20, greater than 25, greater than 30, greater than 35, greater than 40, greater than 45, or greater than 50 ring members.

[0044] In some aspects, the first bond is a dynamic covalent bond. In some aspects, the first bond is a sulfur-sulfur bond, an oxygen-oxygen bond, a nitrogen-nitrogen bond, a silicon-sulfur bond, a silicon-silicon bond, a phosphorus-phosphorus bond, an oxygen-sulfur bond, a nitrogen-phosphorus bond, a carbon-phosphorus bond, a phosphorus-silicon bond, a carbon-sulfur bond, a nitrogen-oxygen bond, and combinations thereof. In some aspects, the first bond is a non-polar covalent bond or a polar covalent bond. In some aspects, the bond dissociation energy of the first bond is measured as a bond dissociation energy or a bond breaking energy.

[0045] In some aspects, the polymer chains are hydrophobic. In certain aspects, the first bond has a strength of less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond in polyethylene.

[0046] In various aspects, the present disclosure provides a polymeric material comprising a composition as described herein. In various aspects, the present disclosure provides a polymeric material comprising: a ring comprising three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol.

[0047] In various aspects, the present disclosure provides a polymeric material comprising: a ring comprising three or more ring members; a first bond located between a first set of two ring members, wherein upon catalyst activation, the first bond is convertible into a bond having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol.

[0048] In some aspects, the polymeric material further comprises a catalyst. In some aspects, the polymeric material comprises less than 10wt%, less than 9wt%, less than 8wt%, less than 7wt%, less than 6wt%, less than 5wt%, less than 4wt%, less than 3wt%, less than 2wt% or less than 1wt% hydrogen bonding units. In some aspects, the polymeric material comprises less than 10wt%, less than 5wt%, less than 1wt% or less than 0.5wt% water after being placed in an aqueous environment for 24 hours at 37°C.

[0049] In some aspects, the polymeric material is hydrophobic. In some aspects, the polymeric material comprises a plurality of rings, each of the rings comprising: three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol. In some aspects, the polymeric material comprises greater than 0.1 wt%, greater than 0.5 wt%, greater than 1 wt%, greater than 2 wt%, greater than 3 wt%, greater than 4 wt%, greater than 5 wt%, greater than 6 wt%, greater than 7 wt%, greater than 8 wt%, greater than 9 wt%, greater than 10 wt%, greater than 15 wt%, greater than 20 wt%, greater than 25 wt%, greater than 30 wt%, greater than 35 wt%, greater than 40 wt%, greater than 45 wt%, greater than 50 wt%, greater than 60 wt%, or greater than 70 wt% of one or more rings.

[0050] In some aspects, the polymeric material is characterized by one or more of the following: a tensile modulus greater than or equal to 100 MPa after being placed in an aqueous environment at 37°C for 24 hours; a tensile strength at yield greater than or equal to 5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a storage modulus greater than or equal to 300 MPa after being placed in an aqueous environment at 37°C for 24 hours; a residual bending stress after 24 hours greater than or equal to 1.5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a hardness of 60 Shore A to 85 Shore D after being placed in an aqueous environment at 37°C for 24 hours; and an elongation at break greater than or equal to 15% after being placed in an aqueous environment at 37°C for 24 hours.

[0051] In some aspects, the polymeric material is characterized by a residual bending stress greater than 5% when tested in a humid environment at 37° C. for 24 hours. In some aspects, the polymeric material is characterized by a residual stress of 5% to 45% of the initial load, or a residual stress of 20% to 45% of the initial load after testing in a humid environment at 37° C. for 24 hours. In some aspects, the polymeric material is characterized by a tensile modulus of 100 MPa to 3000 MPa, 100 MPa to 2500 MPa, 100 MPa to 2000 MPa, 500 MPa to 3000 MPa, 500 MPa to 2500 MPa, 500 MPa to 2000 MPa, 750 MPa to 3000 MPa, 750 MPa to 2500 MPa, or 750 MPa to 2000 MPa after testing in a humid environment at 37° C. for 24 hours. In some aspects, the polymeric material is characterized by an elongation at break greater than 10%, an elongation at break greater than 20%, an elongation at break greater than 30%, an elongation at break of 5% to 250%, an elongation at break of 20% to 250%, or an elongation at break of 40% to 250%, after testing in a humid environment at 37°C for 24 hours. In some aspects, the polymeric material is characterized by a storage modulus of 0.1 MPa to 4000 MPa, a storage modulus of 300 MPa to 3000 MPa, or a storage modulus of 750 MPa to 3000 MPa, after testing in a humid environment at 37°C for 24 hours. In some aspects, the polymeric material is characterized by a residual stress of 0.01 MPa to 15 MPa, or a residual stress of 2 MPa to 15 MPa, after testing in a humid environment at 37°C for 24 hours. In some aspects, greater than 70% of visible light passes through the polymeric material. In some aspects, the polymeric material is biocompatible, bioinert, or a combination thereof.

[0052] In various aspects, the present disclosure provides an orthodontic appliance comprising a polymeric material as described herein. In various aspects, the present disclosure provides an orthodontic appliance comprising a composition as described herein. In some aspects, the orthodontic appliance is an aligner, an expander, or a spacer. In some aspects, the orthodontic appliance comprises a plurality of tooth receiving cavities configured to reposition teeth from a first configuration toward a second configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration according to a treatment plan. In some aspects, the orthodontic appliance is an aligner.

[0053] In various aspects, the present disclosure provides a resin comprising: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 30 kDa; and a ring monomer comprising: three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group.

[0054] In various aspects, the present disclosure provides a resin comprising: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 30 kDa; a cyclic monomer comprising: three or more ring members; a first bond located between a first set of two ring members, wherein upon catalyst activation, the first bond is convertible to a bond having a bond dissociation energy of less than 325 kJ / mol; a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group.

[0055] In some aspects, the resin further comprises a catalyst. In some aspects, the resin further comprises an initiator. In some aspects, the first joint and the second joint are each covalently attached to the ring. In some aspects, the first joint and the second joint are each positioned outside the ring. In some aspects, the resin comprises an oligomer having an average chain length of 1 kDa to 30 kDa, and the oligomer comprises at least some of the plurality of monomers.

[0056] In some aspects, the initiator is a photoinitiator, a thermal initiator, or a combination thereof. In some aspects, the first reactive group, the second reactive group, or a combination thereof comprises an acrylate, a methacrylate, a thiol, an epoxide, an allyl ether, a hydroxyl group, an amine, a derivative thereof, and a combination thereof. In some aspects, the bond dissociation energy of the first bond is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In some aspects, the oligomer comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the first bond. In some aspects, the ring includes a plurality of keys between the groups of two ring members, and the bond dissociation energy of each of the plurality of keys is higher than the bond dissociation energy of the first key by at least 20kJ / mol, at least 30kJ / mol, at least 40kJ / mol, at least 50kJ / mol, at least 60kJ / mol, at least 70kJ / mol, at least 80kJ / mol, at least 90kJ / mol, at least 100kJ / mol, at least 125kJ / mol, at least 150kJ / mol, at least 175kJ / mol or at least 200kJ / mol. In some aspects, the first key is selected from sulphur-sulphur bond, oxygen-oxygen bond, nitrogen-nitrogen bond, silicon-sulphur bond, silicon-silicon bond, phosphorus-phosphorus bond, oxygen-sulphur bond, nitrogen-phosphorus bond, carbon-phosphorus bond, phosphorus-silicon bond, carbon-sulphur bond, nitrogen-oxygen bond and combinations thereof. In some aspects, the first key is a non-polar covalent bond or a polar covalent bond.

[0057] In some aspects, the resin comprises less than 10 wt% hydrogen bonding units. In some aspects, the resin further comprises a reactive diluent, a crosslinking modifier, a light blocker, a solvent, a glass transition temperature modifier, a thermal initiator, or a combination thereof. In some aspects, the resin further comprises at least one of a polymerization catalyst, an inhibitor, a plasticizer, a surface energy modifier, a pigment, a dye, a filler, a seed crystal, a crystallization catalyst, a bioagent, a catalyst for selective bond breaking, or any combination thereof.

[0058] In some aspects, the oligomer includes a polymerizable group. In some aspects, the polymerizable group of the oligomer is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, derivatives thereof, and combinations thereof. In some aspects, the resin has a viscosity of 0.5 PaS to 20 PaS at a printable temperature. In some aspects, the printable temperature is 70°C to 110°C. In some aspects, the printable temperature is 90°C. In some aspects, the resin is capable of 3D printing.

[0059] In various aspects, the present disclosure provides a method for forming a polymeric material, comprising: providing a resin disclosed herein; and curing the resin with a light source, thereby forming the polymeric material. In some aspects, the method further comprises providing a catalyst for forming weak bonds. In some aspects, the polymeric material is a polymeric material disclosed herein. In some aspects, the polymeric material comprises a composition described herein.

[0060] In some aspects, the method further comprises fabricating the object from the polymeric material and / or composition. In some aspects, fabricating comprises printing using a 3D printer. In some aspects, fabricating comprises thermal lithography. In some aspects, fabricating comprises digital light projection.

[0061] In some aspects, the object is an orthodontic appliance. In some aspects, the orthodontic appliance is an aligner, expander, or spacer. In some aspects, the orthodontic appliance includes a plurality of tooth sockets configured to reposition teeth from a first configuration to a second configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration. In some aspects, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration according to a treatment plan. In some aspects, the object is an orthodontic appliance as described herein. In some aspects, the object is an aligner.

[0062] In various aspects, the present disclosure provides a polymeric material produced by the methods described herein. In some aspects, the stress applied to the polymeric material or composition breaks a first bond before breaking a second bond.

[0063] In various aspects, the present disclosure provides a method of repositioning a patient's teeth, the method comprising: applying an orthodontic appliance disclosed herein to at least one of the patient's teeth; and moving at least one of the patient's teeth toward an intermediate or final tooth arrangement.

[0064] In various aspects, the present disclosure provides a method for repositioning a patient's teeth, the method comprising: generating a treatment plan for the patient, the plan comprising a plurality of intermediate tooth arrangements for moving the teeth from an initial arrangement to a final arrangement along a treatment path; producing a 3D printed orthodontic appliance comprising: a ring comprising three or more ring members; a first bond positioned between a first set of two ring members and having a bond dissociation energy less than 325 kJ / mol; and a second bond positioned between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol; and moving at least one tooth of the patient along the path toward an intermediate arrangement or a final tooth arrangement using the orthodontic appliance.

[0065] In various aspects, the present disclosure provides a method for repositioning a patient's teeth, the method comprising: generating a treatment plan for the patient, the plan comprising a plurality of intermediate tooth arrangements for moving the teeth from an initial arrangement to a final arrangement along a treatment path; producing an orthodontic appliance as described herein; and using the orthodontic appliance to move at least one tooth of the patient along the path toward an intermediate arrangement or a final tooth arrangement, wherein the first bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol.

[0066] In some aspects, the method further comprises tracking the progress of the patient's teeth along the treatment path after applying the orthodontic appliance, the tracking comprising comparing the current arrangement of the patient's teeth with the planned arrangement of the teeth. In some aspects, after 2 weeks of treatment, greater than 60% of the patient's teeth conform to the treatment plan. In some aspects, the orthodontic appliance has a retained repositioning force on at least one of the patient's teeth of at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 70% of the repositioning force initially provided to the at least one tooth of the patient after 2 days. In some aspects, the method further comprises achieving movement of at least one of the patient's teeth to an intermediate arrangement or a final tooth arrangement along the path.

[0067] In some aspects, producing comprises direct manufacturing, and optionally, wherein direct manufacturing comprises cross-linking the printable resin described herein. In some aspects, the 3D printed orthodontic appliance is an orthodontic appliance described herein.

[0068] In various aspects, the present disclosure provides a composition comprising: a ring monomer comprising: three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; a second bond located between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group.

[0069] In various aspects, the present disclosure provides a composition comprising: a cyclic monomer comprising: three or more ring members; a first bond positioned between a first set of two ring members, wherein upon catalyst activation, the first bond is convertible into a bond having a bond dissociation energy of less than 325 kJ / mol; a second bond positioned between a second set of two ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group.

[0070] In some aspects, the composition further comprises a catalyst. In some aspects, the composition further comprises an initiator. In some aspects, the first joint and the second joint are each covalently attached to the ring. In some aspects, the first joint and the second joint are each positioned outside the ring. In some aspects, the first reactive group, the second reactive group, or a combination thereof comprises acrylate, methacrylate, thiol, epoxide, allyl ether, hydroxyl, amine, its derivatives and combinations thereof. In some aspects, the bond dissociation energy of the first bond is less than or equal to 300kJ / mol, less than or equal to 275kJ / mol, less than or equal to 250kJ / mol, less than or equal to 225kJ / mol, less than or equal to 200kJ / mol, less than or equal to 175kJ / mol, less than or equal to 150kJ / mol, 50kJ / mol to 300kJ / mol, 55kJ / mol to 250kJ / mol, or 60kJ / mol to 200kJ / mol. In some aspects, the ring includes a plurality of keys between the groups of two ring members, and the bond dissociation energy of each of the plurality of keys is higher than the bond dissociation energy of the first key by at least 20kJ / mol, at least 30kJ / mol, at least 40kJ / mol, at least 50kJ / mol, at least 60kJ / mol, at least 70kJ / mol, at least 80kJ / mol, at least 90kJ / mol, at least 100kJ / mol, at least 125kJ / mol, at least 150kJ / mol, at least 175kJ / mol or at least 200kJ / mol. In some aspects, the first key is selected from sulphur-sulphur bond, oxygen-oxygen bond, nitrogen-nitrogen bond, silicon-sulphur bond, silicon-silicon bond, phosphorus-phosphorus bond, oxygen-sulphur bond, nitrogen-phosphorus bond, carbon-phosphorus bond, phosphorus-silicon bond, carbon-sulphur bond, nitrogen-oxygen bond and combinations thereof. In some aspects, the first key is a non-polar covalent bond or a polar covalent bond. In some aspects, the composition comprises less than 10 wt% hydrogen bonding units. In some aspects, the composition is capable of being 3D printed.

[0071] Incorporation by reference

[0072] All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

[0073] BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1A A tooth repositioning appliance according to an embodiment is shown.

[0075] Figure 1B A tooth repositioning system according to an embodiment is shown.

[0076] Figure 1C An orthodontic treatment method using multiple appliances according to an embodiment is shown.

[0077] Figure 2 A method for designing an orthodontic appliance according to an embodiment is shown.

[0078] Figure 3 A method for digitally planning orthodontic treatment according to an embodiment is shown.

[0079] Figure 4 The generation and administration of a therapeutic according to one embodiment of the present invention is shown.

[0080] Figure 5 Exemplary bond dissociation energies are shown.

[0081] Figure 6 A two-dimensional representation of the structure of a cross-linked network comprising weakly cross-linked units and strongly cross-linked units is shown.

[0082] Figure 7A An exemplary synthesis of nitrogen-based weak crosslinking unit monomers is shown. Figure 7B Exemplary nitrogen-based weak crosslinking units are shown. Figure 7C Exemplary sulfur-based weak crosslinking units are shown. Figure 7D Exemplary diketone-based weak cross-linking units are shown.

[0083] Figure 8A An exemplary synthesis of a Diels-Alder adduct as a weakly cross-linking unit is shown. Figure 8B Exemplary adducts incorporated into polymer networks are shown. Figure 8C Shown is the tension applied to a polymer network comprising weakly cross-linked units. Figure 8D The dissociation of weakly cross-linked units upon application of tension is shown. Figure 8E and Figure 8F Each shows the synthesis of an exemplary Diels-Alder adduct.

[0084] Figure 9A Shown is the polymerization of an exemplary polymer network comprising reactive functional groups. Figure 9B Weakly cross-linked units are shown attached to the polymer network after initial curing.

[0085] Figure 10A An example of a resin including a first monomer including a first weak bond forming unit and a second monomer including a strong-weak bond forming unit and a combination thereof to form a weak cross-linked bond is shown. Figure 10B A resin further comprising a third monomer comprising a first strong bond-forming unit and a fourth monomer comprising a second strong bond-forming unit, and a combination thereof to form a strong cross-linked bond is shown.

[0086] Figure 11 Shown is a two-dimensional representation of a polymer containing rings comprising weak bridges containing weak bonds.

[0087] Figure 12 Exemplary ring monomers containing weak bonds are shown.

[0088] Figure 13A Exemplary ring monomers containing weak bonds are shown. Figure 13B Exemplary cyclic monomers incorporated into polymer chains are shown. Figure 13C The strain applied to a polymer chain comprising a cyclic monomer is shown. Figure 13D The dissociation of weak bonds upon application of tension is shown.

[0089] Figures 14A-14F An exemplary ring monomer is shown that includes a weak bond, represented by a dashed arrow. Figure 14A A cyclopropane ring containing a weak bond is shown. Figure 14B Spiropyrans containing weak bonds are shown. Figure 14C A cyclohexane ring containing a weak bond is shown. Figure 14D Ring monomers containing ionic bridges as weak bonds are shown. Figure 14E A ring monomer containing a weak carbon-sulfur bond in a weak bridge is shown. Figure 14F A ring monomer comprising a weak bridge comprising a double hydrogen bond as the weak bond is shown.

[0090] Figure 15A -C shows an exemplary ring monomer comprising multiple weak bonds and / or multiple rings. Figure 15A A cyclic monomer containing multiple rings containing weak bonds is shown. Figure 15B A cyclic monomer containing multiple weak bonds located on the ring is shown. Figure 15C A cyclic monomer comprising two rings sharing a weak bond is shown.

[0091] Detailed description of the invention

[0092] A. Weak covalent crosslinking

[0093] The present disclosure provides a polymer material comprising a weak cross-linked covalent bond and / or a weak cross-linked unit comprising a weak covalent bond. Use weak covalent bonds to replace the hydrogen bonds present in traditional polymer materials (e.g., polyurethanes). Advantageously, toughness can be controlled by changing the intensity of the weak covalent bond and / or by changing the number of weak covalent crosslinks. The cross-linked material using weak covalent crosslinks can be used to manufacture a toughness material that can resist stress relaxation.

[0094] It has been found that polymeric materials formed from polymers with high levels of hydrogen bonding (e.g., polyurethanes) may be susceptible to exposure to aqueous environments. Hydrogen bonding units tend to absorb water, acting as plasticizers and reducing the ability of polymers to resist creep or stress. Hydrogen bonds are dynamic bonds, and in the presence of water, hydrogen bonds become more dynamic and weaker, thereby reducing the toughness of the material in the presence of water. Therefore, materials that are manufactured for use in humid environments using hydrogen bonds (e.g., orthodontic appliances such as aligners placed in the oral cavity) may be susceptible to exposure to aqueous environments. By applying weak covalent crosslinking to form polymeric materials disclosed herein, products for use in humid or aqueous environments can be produced that have increased durability and / or improved functionality compared to standard polyurethanes. Therefore, the materials disclosed herein are tough and are not susceptible to reduced toughness in the presence of water.

[0095] The polymeric materials of the present invention can simulate the positive effects (such as toughness) caused by the accumulation of hydrogen bonds along the polymer chain without producing the negative consequences of relying on hydrogen bonds. These polymeric materials maintain toughness even in the presence of water. In some embodiments, the polymeric materials described herein are hydrophobic tough materials including weak covalent cross-links; optionally, wherein the weak covalent cross-links are dynamic bonds. Polymer materials incorporating weak covalent bonds (which may also be dynamic) have advantages such as selective stress concentration. As a non-limiting example, a polymer subjected to stress (e.g., by tensile stress) concentrates stress on weak cross-links; if the bond strength of the cross-links is lower than the bond strength of the polymer backbone, the cross-links will break, thereby protecting the integrity of the polymer chains. In this way, the breakage in the cross-links prevents the main chain from breaking, which in turn prevents crack formation and allows the polymer to stretch further, thereby producing a tough material. When dynamic weak covalent bonds are used, the material can reform these bonds after stress is applied.

[0096] It was also observed that the resins forming the polymeric materials disclosed herein have low viscosities compared to polymeric resins with high levels of hydrogen bonding. Monomers with high levels of hydrogen bonding groups impart increased viscosity to the resins, which in turn can reduce printing speeds when using, for example, direct manufacturing to produce products. By using the resins disclosed herein, printing speeds can be increased, thereby reducing the time it takes to produce direct manufacturing products.

[0097] High viscosity printable resins for forming tough devices traditionally require specialized equipment, such as high temperature 3D printers for thermal lithography. Customized 3D printers (e.g., high temperature 3D printers) can be expensive, and the products formed therefrom require rigorous post-processing steps. The low viscosity resins described herein are suitable for conventional printers using conventional post-processing. This can facilitate the use of resins for the production of materials that otherwise might require the use of expensive and custom equipment.

[0098] I. Polymer Materials

[0099] i. Weakly cross-linked units.

[0100] The present disclosure provides a polymer material comprising a weak cross-linking unit connecting a polymer chain. In some embodiments, the weak cross-linking unit comprises a first end, a second end and a weak covalent bond between the first end and the second end. In some embodiments, the weak cross-linking unit is a weak covalent bond. The weak covalent bond is weaker than the covalent bond of the polymer backbone. The non-limiting example of the polymer backbone is polyacrylate, whose carbon-carbon bond tends to have a bond dissociation energy of 340kJ / mol to 360kJ / mol. In a preferred embodiment, the weak covalent bond is thermally stable at room temperature and / or human body temperature (for example, human oral temperature). The weak covalent bond as herein described and the weak cross-linking unit comprising the weak covalent bond make the polymer (for example, polyacrylate) cross-linked.

[0101] Conventional polymeric materials (e.g., polyurethanes) have hydrogen bonds with bond strengths ("bond dissociation energies") that are typically in the range of 8 to 30 kJ / mol. Hydrogen bonds are dynamic at room temperature (i.e., they can be broken and reformed). In some embodiments, the weak covalent bonds further described herein have bond dissociation energies of 10 to 340 kJ / mol, preferably 60 to 200 kJ / mol. In some embodiments, the weak covalent bonds further described herein are dynamic bonds. As used herein, the terms "bond strength" and "bond dissociation energy" refer to bond dissociation energies. Other tools can be used to measure bond strength, including the use of heterolytic bond breakage energies or molecular modeling to estimate bond dissociation energies. Exemplary bond dissociation energies are Figure 5 shown.

[0102] In some embodiments, the bond dissociation energy of the weak covalent crosslink ("weak crosslink" or "weak covalent bond") is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, or less than or equal to 150 kJ / mol. In some embodiments, the bond dissociation energy of the weak crosslink is from 50 kJ / mol to 325 kJ / mol, from 50 kJ / mol to 300 kJ / mol, from 55 kJ / mol to 250 kJ / mol, or from 60 kJ / mol to 200 kJ / mol. In certain embodiments, the weak covalent crosslink has a thermal decomposition temperature below 350°C. In some embodiments, the thermal decomposition temperature of the weak crosslink is lower than the thermal decomposition temperature of the first polymer chain and / or the thermal decomposition temperature of the second polymer chain.

[0103] In some embodiments, the weak cross-link is a dynamic covalent bond. In some embodiments, the weak cross-link unit comprises a dynamic covalent bond.

[0104] In some embodiments, the weak crosslinks are selected from the group consisting of sulfur-sulfur bonds, oxygen-oxygen bonds, nitrogen-nitrogen bonds, silicon-sulfur bonds, silicon-silicon bonds, phosphorus-phosphorus bonds, oxygen-sulfur bonds, nitrogen-phosphorus bonds, carbon-phosphorus bonds, phosphorus-silicon bonds, carbon-sulfur bonds, nitrogen-oxygen bonds, and combinations thereof.

[0105] In some embodiments, weak cross-linking bonds are attached to one or more stable molecular structures. In some embodiments, weak cross-linking bonds are attached to 1, 2, 3 or more stable molecular structures. In certain embodiments, each side of a weak cross-linking bond is attached to at least one stable molecular structure. The free radicals or ions formed after the stable molecular structure stable bond breaks. See: McMillen et al., Hydrocarbon Bond Dissociation Energies, Ann.Rev.Phys.Chem., 1982, 33: 493-532, which is incorporated herein by reference. The weak cross-linking bond can be, for example, a carbon-carbon bond between two stable molecular structures. As a non-limiting example, the carbon-carbon bond of 1,1,2,2-tetraphenylethane has a bond dissociation energy of 247.3 ± 8.4 kJ / mol, while the carbon-carbon bond of ethane has a bond dissociation energy of 377.4 ± 0.8 kJ / mol. See: Luo, Yu-Ran "Handbook of Bond Dissociation Energies in Organic Compounds" CRC Press, 2002, which is incorporated herein by reference. In some embodiments, the weak cross-linked bond is a carbon-carbon bond. In certain embodiments, the weak cross-linked bond is a carbon-carbon bond, in which one or two carbon atoms are attached to one, two or more stable molecular structures. In some embodiments, the weak cross-linked bond is a carbon-carbon bond, in which two carbon atoms are each attached to at least one stable molecular structure. In some embodiments, the stable structure is an aromatic ring. In certain embodiments, the stable structure includes benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cinnoline, phthalazine, 1,2,3-triazine, 1,2,4-triazine, s-triazine, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole, or thiazole.

[0106] In some embodiments, the weak cross-linked bond is a non-polar covalent bond or a polar covalent bond. In certain embodiments, the weak cross-linked bond is an ionic bond. In some embodiments, the weak cross-linked bond is an organometallic bond. Exemplary organometallic bonds have bond dissociation energies as described in Basch "Bond dissociation energies in organometallic compounds" Inorganica ChimaActa 252 (1996) 265-279, which is incorporated herein by reference. In some embodiments, the weak cross-linked bond is a heterolytic bond. Exemplary heterolytic bonds have bond dissociation energies as described in Kitagawa et al., "Structural dependence of heterolytic bond dissociation energy ofσcarbon-carbon bonds in hydrocarbons" Journal of Physical Organic Chemistry, 11 (1998), 157-170, which is incorporated herein by reference.

[0107] In some embodiments, the weak crosslinks have less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the strength of the average carbon-carbon bonds in polyethylene.

[0108] In certain embodiments, the bond dissociation energy of a weak cross-link is measured as a bond dissociation energy or a bond breakage energy.

[0109] ii. Composition of polymer materials

[0110] In some embodiments, the present disclosure provides a polymeric material comprising:

[0111] a first polymer chain;

[0112] a second polymer chain; and

[0113] A weak cross-linking unit attached to a first polymer chain at a first end of the weak cross-linking unit and to a second polymer chain at a second end of the weak cross-linking unit, the weak cross-linking unit comprising a weak cross-linking bond between the first end and the second end. In some embodiments, the weak cross-linking bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In certain embodiments, the weak cross-linking unit is a weak cross-linking bond. Figure 6Shown is a representation of a cross-linked polymer material comprising a weak cross-linking unit attached to a first polymer chain at a first end and to a second polymer chain at a second end, including a weak bond between the first and second ends.

[0114] In some embodiments, the polymeric material comprises a plurality of weak crosslinking units. In certain embodiments, the polymeric material comprises a plurality of weak crosslinking units that are arranged to crosslink between a first polymer chain and a second polymer chain. In some embodiments, the plurality of weak crosslinking units are dispersed throughout the polymeric material. In some embodiments, the plurality of weak crosslinking units are attached to the first polymer chain at a first end and to the second polymer chain at a second end.

[0115] In some embodiments, the present disclosure provides a polymeric material comprising:

[0116] a first polymer chain;

[0117] a second polymer chain; and

[0118] A weak cross-linked bond attached to a first polymer chain at a first end and to a second polymer chain at a second end. In some embodiments, the weak cross-linked bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some embodiments, the polymeric material comprises a plurality of weak cross-linked bonds. In certain embodiments, the plurality of weak cross-linked bonds are attached to a first polymer chain at a first end and to a second polymer chain at a second end.

[0119] In certain embodiments, the present disclosure provides a polymeric material comprising:

[0120] a first polymer chain;

[0121] a second polymer chain; and

[0122] Activatable unit, it is attached to the first polymer chain at the first end and is attached to the second polymer chain at the second end.Activatable unit is a unit that can be converted into a unit comprising a weak cross-linking bond. For example, activatable unit can be a unit without a weak cross-linking bond, and after activation, the unit includes a weak cross-linking bond. In some embodiments, when activated by catalyst, reagent and / or reactant, activatable unit is converted into a weak cross-linking unit (that is, activated). In some embodiments, gained weak cross-linking unit is attached to the first polymer chain at the first end, and is attached to the second polymer chain at the second end, and weak cross-linking unit includes the weak cross-linking bond between the first end and the second end. In some embodiments, weak cross-linking bond has a bond dissociation energy of 50kJ / mol to 325kJ / mol. In certain embodiments, weak cross-linking unit is a weak cross-linking bond.

[0123] In some embodiments, the catalyst acts on the polymer material to produce weak covalent cross-links and / or weak cross-linked units comprising weak covalent bonds. As a non-limiting example, the polymer material can be made up of relatively strong bonds (i.e., there are no weak covalent bonds), but after the catalyst is added, there are weak covalent bonds. As a non-limiting example, the polymer material may include cross-linked units / bonds comprising esters, which are extremely stable bonds; after adding water and a weak acid (i.e., in this case, water is a reagent and the acid is a catalyst), when placed under pressure, the ester breaks more effectively (i.e., hydrolyzes); therefore, in the presence of water and acid, the ester becomes a weak chain. The bond strength of disulfide bonds and esters is reduced in the presence of metal ions and / or Lewis acids and / or by changes in pH. In some embodiments, the weak covalent cross-links include disulfides or esters, and the catalyst includes metal ions, Lewis acids, pH changes, or any combination thereof. In this way, the polymer material can be formed without weak covalent bonds, but after adding the catalyst, the polymer material includes weak covalent bonds. In some embodiments, the catalyst selectively reduces the bond dissociation energy of the cross-links and / or weak cross-linking units, thereby forming weak cross-links and / or weak cross-linking units comprising weak cross-links, respectively, in the presence of the catalyst.

[0124] In some embodiments, the catalyst selectively reorganizes the bond. As a non-limiting example, a polymer material comprising a disulfide cross-link (i.e., a dynamic covalent bond) can be activated by a photoinitiator (i.e., a catalyst) under stress. The free radicals from the photoinitiator can destroy the disulfide bond, and then reorganize and reform a new disulfide bond. In this way, stress is released from the system only by releasing stress from the disulfide bond. This allows selective bond rupture, which maintains the strength of the polymer material by preventing the bond rupture of the polymer backbone. In some embodiments, the catalyst disclosed herein rearranges weak cross-linked covalent bonds. Another non-limiting example is the addition of an intrachain peroxide combined with an aromatic disulfide, which produces a rapid reorganization of the cross-linked network. In this non-limiting example, when the intrachain peroxide bond breaks (the concentration of the peroxide is relatively low relative to the disulfide bond concentration), the peroxy radical catalyzes the disulfide bond cleavage reaction. Therefore, in this non-limiting example, the rupture of a weak covalent bond (peroxide bond) leads to the rupture of multiple bonds (e.g., disulfide bonds). In this non-limiting example, when the stress is removed or when all free radicals are removed, reacted, or trapped, the broken disulfide bonds can reform into stable covalent bonds.

[0125] In some embodiments, the catalyst selectively reduces the bond dissociation energy of the cross-links and / or weak cross-linking units, thereby forming weak cross-links and / or weak cross-linking units comprising weak cross-links, respectively, in the presence of the catalyst.

[0126] In some embodiments, the polymeric material further comprises a catalyst. In some embodiments, the polymeric material is formed from a resin comprising a catalyst. In some embodiments, the resin comprising a catalyst comprises an intrachain catalyst. A non-limiting example of an intrachain catalyst is an intrachain peroxide as described above. For example, an intrachain peroxide can break disulfide bonds in the presence of disulfide bonds, catalyzing a disulfide bond cleavage reaction that can reform a stable covalent bond when the stress is removed or when all free radicals are removed, reacted, or trapped.

[0127] In some embodiments, the first polymer chain, the second polymer chain, or each of the first and second polymer chains comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links. In some embodiments, the first polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links. In some embodiments, the second polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links.

[0128] In some embodiments, the first polymer chain, the second polymer chain, or each of the first polymer chain and the second polymer comprises a backbone wherein all covalent bonds in the backbone have a bond dissociation energy greater than 280 kJ / mol or greater than 300 kJ / mol.

[0129] In some embodiments, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the first polymer chain, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In some embodiments, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the first polymer chain, wherein the ratio is from 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:100 to 1:200, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500.

[0130] In certain embodiments, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the second polymer chain, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, or less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In certain embodiments, the polymeric material comprises a ratio of the longest length of the weak crosslink unit to the longest length of the second polymer chain, wherein the ratio is from 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:100 to 1:200, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500.

[0131] In some embodiments, the polymer material also includes a strong cross-linking unit. The polymer material comprising both a strong cross-linking unit and a weak cross-linking unit can have the advantageous property of increasing strength while retaining a weak covalent bond that can be selectively broken when stress is applied. In some embodiments, the strong cross-linking unit is attached to the first polymer chain at the first end, and the strong cross-linking unit is attached to the second polymer chain at the second end, and the strong cross-linking unit includes forming one or more keys of the chain connected to the first end and the second end. In certain embodiments, each of the one or more keys has a bond dissociation energy greater than or equal to 275kJ / mol. In some embodiments, each of the one or more keys has a bond dissociation energy greater than or equal to 300kJ / mol.

[0132] In certain embodiments, the polymeric material comprises a ratio of the number of strongly crosslinked units to the number of weakly crosslinked units, wherein the ratio is from 1:50 to 5:1, 1:40 to 2:1, 1:30 to 1:1, 1:25 to 1:1, 1:20 to 1:1, 1:15 to 1:1, 1:10 to 1:1, 1:5 to 1:1, 1:30 to 1:5, 1:25 to 1:5, 1:20 to 1:5, 1:20 to 1:10, or 1:10 to 1:5. In some embodiments, the ratio is from 1:20 to 1:5. In some preferred embodiments, the ratio is from 1:20 to 1:10. In some preferred embodiments, the ratio is about 1:10. In some embodiments, the ratio is less than 1:50. In some embodiments, the ratio is greater than 1:1, greater than 2:1, greater than 3:1, greater than 4:1, or greater than 5:1. In certain aspects, additional ratios of the number of strong cross-linked units to the number of weak cross-linked units are contemplated. Generally, the ratio of the number of strong cross-linked units to the number of weak cross-linked units will depend on the specific formulation and the specific properties desired, and can be selected by one of ordinary skill in the art to suit a particular application.

[0133] In some embodiments, the polymeric material comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of weak crosslinking units. In some embodiments, the polymeric material comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of weak crosslinking bonds. In some preferred embodiments, the polymeric material comprises greater than 0.1 wt% of weak crosslinking bonds. In some preferred embodiments, the polymeric material comprises greater than 50 wt% weak crosslinks. The weight percentage of weak crosslink units and / or weak crosslinks can preferably be calculated or measured by the weight percentage of weak crosslink groups. As a non-limiting example, the SS of a disulfide bond acts as a weak crosslink unit; thus, a polymeric material having less than 1 wt% crosslinked SS units has less than 1 wt% weak crosslink units.

[0134] In some embodiments, the polymeric material includes a ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chains, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10. In some embodiments, the ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chains is 1:1000 to 1:100, 1:900 to 1:150, 1:800 to 1:200, or 1:750 to 1:250.

[0135] In some embodiments, the polymeric material includes a ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the second polymer chains, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10. In certain embodiments, the ratio of the total number of bonds of the weak crosslinking units to the total number of bonds of the first polymer chains is 1:1000 to 1:100, 1:900 to 1:150, 1:800 to 1:200, or 1:750 to 1:250.

[0136] Some polymeric materials traditionally used to make appliances (e.g., orthodontic appliances) include high levels of hydrogen bonding units (e.g., urethanes, ureas, amides, hydroxyls, amines, carbonyl-based acids, phosphorus-based acids, sulfur-based acids, poly(ethylene glycol) ethers, or derivatives thereof). In some embodiments, the polymeric materials disclosed herein contain less than 10 wt%, less than 9 wt%, less than 8 wt%, less than 7 wt%, less than 6 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, or less than 1 wt% hydrogen bonding units. The percentage of hydrogen bonding units can preferably be calculated or measured by the weight percentage of hydrogen bonding groups. As a non-limiting example, the NHCO of an amide bond acts as both a hydrogen donor and a hydrogen acceptor; therefore, a polymeric material having less than 10 wt% NHCO units (without other types of hydrogen bonding units) has less than 10 wt% hydrogen bonding units. Alternatively, the value of wt% hydrogen bonding units can be determined by performing a titration to obtain the number of hydrogen bonding groups. In a preferred embodiment, the polymeric material contains less than 5 wt% hydrogen bonding units. In a more preferred embodiment, the polymeric material comprises less than 2 wt% hydrogen-bonding units. In some more preferred embodiments, the polymeric material comprises substantially no hydrogen-bonding units. A low amount of hydrogen-bonding units in the polymeric material can result in the polymeric material having a relatively low level of water absorption, as the presence of the hydrogen-bonding units promotes such absorption. Advantageously, resins with reduced hydrogen-bonding groups tend to have lower viscosities than base polymers with the same hydrogen-bonding groups, which can improve the practicality of using, for example, stereolithography 3D printers.

[0137] The polymeric materials described herein have a low level of water absorption. This low level of water absorption is advantageous for the polymeric materials described herein. Water absorption occurs when the polymeric material is exposed to a humid environment (e.g., the mouth of a patient using an orthodontic appliance formed from a polymeric material). Traditional polymeric materials with high levels of hydrogen bonding are advantageous for water absorption because water is attracted to hydrogen bonding groups; water molecules are also attracted to polar atoms. In some embodiments, the polymeric materials disclosed herein have weak covalent bonds with low polarity atoms or non-polar atoms, thereby minimizing water absorption. In certain embodiments, the polymeric material includes polar atoms in the weak covalent bonds, but the bonds are minimally disrupted to not disrupted by water, thereby maintaining the integrity of the polymeric material. When water absorption reaches a threshold value (typically greater than 22 wt%), the performance of the polymeric material degrades. It is preferred herein that the polymeric material have a low level of water absorption. In some embodiments, the polymeric material comprises a water absorption of less than 25 wt%, less than 20 wt%, less than 15 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.25 wt%, or less than 0.1 wt%. In a preferred embodiment, the water absorption is measured after 24 hours in a humid environment at 37°C. In some embodiments, the water absorption is measured using a sample no thicker than 1 mm. In certain embodiments, the water absorption is measured using a sample 1 mm thick. In some embodiments, the polymeric material is hydrophobic.

[0138] In some embodiments, the polymeric material comprises a plurality of first polymer chains having an average chain length of the first polymer chains, and a plurality of weak crosslinking units having an average chain length of the weak crosslinking units, wherein the average chain length of the weak crosslinking units is less than the average chain length of the first polymer chains. In certain embodiments, the polymeric material has a ratio of the average chain length of the weak crosslinking units to the average chain length of the first polymer chains, and wherein the ratio is 1:1.1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:100 to 1:200. 0, less than or equal to 1:1.1, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500.

[0139] In some embodiments, the polymer material includes a plurality of second polymer chains having a second average polymer chain length and a plurality of weak crosslinking units having a weak crosslinking unit average chain length, wherein the weak crosslinking unit average chain length is less than the second average polymer chain length.

[0140] In certain embodiments, the first polymer chain, the second polymer chain, or each of the first and second polymer chains comprises a plurality of monomers, each of which is linked by backbone covalent bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-links.

[0141] In some embodiments, the first polymer chain comprises a plurality of monomers, each monomer being linked by backbone covalent bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-links. In some embodiments, the first polymer chain consists essentially of a plurality of monomers, each of which is connected by backbone covalent bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-links.

[0142] In some embodiments, the second polymer chain comprises a plurality of monomers, each monomer being linked by backbone covalent bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-links. In some embodiments, the second polymer chain consists essentially of a plurality of monomers, each of which is linked by backbone covalent bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-links.

[0143] In some embodiments, the first polymer chain is attached to the weak cross-linking unit by a covalent bond. In some embodiments, the second polymer chain is attached to the weak cross-linking unit by a covalent bond. In some embodiments, each of the first polymer chain and the second polymer chain is attached to the weak cross-linking unit by a covalent bond.

[0144] In some embodiments, the weak crosslinks are dynamic covalent bonds. In certain embodiments of the polymeric material, at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 20%, at least 30%, at least 40%, or at least 50% of the weak crosslinks are dynamic covalent bonds. In some embodiments, the dynamic covalent bonds are free radical dynamic covalent bonds (i.e., weak covalent bonds that break to form free radicals that can combine with other free radicals to reform or form new bonds).

[0145] In certain embodiments, the polymeric material comprises a number ratio of the number of strongly cross-linked units to the number of weakly cross-linked units, wherein the number ratio is greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, or greater than or equal to 50:1. In some embodiments, the polymeric material comprises a ratio of the number of strong crosslink units to the number of weak crosslinks, wherein the ratio is greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, or greater than or equal to 50:1.

[0146] In some embodiments, the polymeric material comprises a ratio of the number of strong crosslinking units to the number of weak crosslinking units, wherein the ratio is 1:100 to 1:1, 1:50 to 1:1, 1:20 to 1:1, 1:10 to 1:1, 1:50 to 50:1, 1:40 to 40:1, 1:30 to 30:1, 1:20 to 20:1, 1:10 to 10:1, 1:1 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:10, 1:10 to 1:100, 1:20 to 1:10 to 1:100, 1:50 to 1:100, greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, greater than or equal to 50:1, or greater than or equal to 1:100. In some embodiments, the polymeric material comprises a ratio of the number of strong crosslinking units to weak crosslinks, wherein the ratio is 1:100 to 1:1, 1:50 to 1:1, 1:20 to 1:1, 1:10 to 1:1, 1:50 to 50:1, 1:40 to 40:1, 1:30 to 30:1, 1:20 to 20:1, 1:10 to 10:1, 1:1 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:1, 1:10 to 1:100, 1:50 to 1:100, 1:10 to 1:100, 1:20 to 1:1 1:100, 1:50 to 1:100, greater than or equal to 1:100, greater than or equal to 1:50, greater than or equal to 1:20, greater than or equal to 1:10, greater than or equal to 1:5, greater than or equal to 1:3, greater than or equal to 1:2, greater than or equal to 1:1, greater than or equal to 2:1, greater than or equal to 3:1, greater than or equal to 5:1, greater than or equal to 10:1, greater than or equal to 20:1, greater than or equal to 50:1, or greater than or equal to 1:100.

[0147] In certain embodiments, the polymeric material has a ratio of an average chain length of weakly crosslinked units to an average chain length of a second polymer chain, and wherein the ratio is from 1:1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:10 to 1:100. In some embodiments, the second polymer chain length is less than or equal to 1:200, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In certain embodiments, the second polymer chain length is greater than the average chain length of the weak crosslink units.

[0148] A polymer material with weak cross-linking units and / or weak cross-linking covalent bonds has a bond weaker than the main chain of the polymer material in the polymer material, so when the material is operated (e.g., pulled), the weak cross-linking units break before the polymer main chain breaks, thereby alleviating stress and maintaining the strength of the polymer main chain. Main chain breakage in the polymer material causes rapid rupture, so the incorporation of weak covalent bonds and / or weak covalent cross-linking units comprising weak covalent bonds prevents breakage. In some embodiments, the stress applied to the polymer material destroys the weak cross-linking bonds before destroying the covalent bonds of the first polymer chain or the second polymer chain. Another non-limiting example of the advantages of weak covalent cross-linking is how it affects the properties of elongation at break. For example, if a polymer with an average chain length of 15,000 is subjected to stress (e.g., tension stretching) and does not have cross-linking, it is assumed that the chain can be reorganized during strain, which may have a high elongation at break. In contrast, the elongation at break of the same polymer with cross-linking of the same or near-same strength as the polymer main chain is lower (depending on the amount of cross-linking - that is, the more cross-linking, the lower the elongation at break). Materials as described herein tend to have an elongation at break between non-crosslinked examples and strongly crosslinked examples. In certain embodiments, the material of weak covalent crosslinking has a higher elongation at break than the sample without crosslinking. Additional properties affected by the presence of weak crosslinking include yield strength (that is, compared to the strongly crosslinked material, when the molar weight of the two is the same, the addition of weak covalent crosslinking will reduce the yield strength). In some embodiments, increasing the concentration of weak covalent crosslinking increases yield strength, but may retain the elongation at break value.

[0149] In some embodiments, weak covalent crosslinking can be used for organic, inorganic or hybrid systems. In certain embodiments, polymer includes organic polymer, inorganic polymer or hybrid polymer. In some preferred embodiments, organic polymer is selected from polyethylene, polypropylene, polybutene, polyisoprene, polyacrylate, polymethacrylate, thioether-containing polymer, polyether, polyester, its copolymer, its mixture, its combination and derivative thereof. In some embodiments, organic polymer includes hydrogen bond system (for example, polyurethane and polyamide), and with the mixture or copolymer of organic polymer as described herein. In some preferred embodiments, inorganic polymer is selected from polysilane, polysiloxane, polyphosphazene, its copolymer, its mixture, its combination and derivative thereof. Hybrid polymer (for example, organic-inorganic polymer) can include any organic polymer and any inorganic polymer, its copolymer, its mixture and derivative thereof.

[0150] B. Intrachain Cyclic Polymers

[0151] The present disclosure provides polymer chains and polymer materials including intrachain loops (also referred to herein as rings), wherein the intrachain loops include weak bonds and / or include weak bridges of at least one weak bond. In some embodiments, the present disclosure provides a composition comprising: a polymer chain comprising: a ring comprising three or more ring members; a first bond (i.e., a weak bond) between two ring members of a first group and having a bond dissociation energy of less than 325 kJ / mol; and a second bond between two ring members of a second group and having a bond dissociation energy greater than 325 kJ / mol. The ring comprises three or more atoms connected in series, and the weak bond is between two atoms of the three or more atoms. In some embodiments, the weak bond (i.e., the first bond) comprises a weak covalent bond. The weak bond is also referred to herein as the first bond. Weak covalent bonds are used instead of the hydrogen bonds present in traditional polymer materials (e.g., polyurethanes). Advantageously, the elongation of tensile strain and / or the elongation at break can be controlled by changing the ring size of the ring (i.e., the number of atoms connected in series in the cyclic structure of the loop). The toughness of the material can be controlled by changing the strength of the weak bond and / or by changing the number of monomers comprising the ring described herein. In some embodiments, the polymer chain is a cross-linking unit arranged between one or more additional polymer chains. In certain embodiments, a ring monomer is a cross-linking unit arranged between two polymer chains. Application of a cross-linked material comprising a ring of weak bonds can be used to produce a tough material that can be elongated and has a lower sensitivity to polymer chain breakage. The ring can be flexible or rigid. Generally, the longer the ring, the greater the elongation in the material. It has been found that polymer materials formed by polymers (such as polyurethanes) with high levels of hydrogen bonds can be harmed by exposure to aqueous environments. Hydrogen bond units tend to absorb water, act as plasticizers and reduce the ability of polymers to resist creep or stress. Hydrogen bonds are dynamic bonds, and in the presence of water, hydrogen bonds become more dynamic and weaker, thereby reducing the toughness of the material in the presence of water. Therefore, materials using hydrogen bonds in humid environments (for example, orthodontic appliances such as aligners placed in the mouth) can be harmed by exposure to aqueous environments. By utilizing weak bonds (e.g., weak covalent bonds) to form the polymeric materials disclosed herein, products for use in wet or aqueous environments can be produced that have increased durability, elasticity, and / or improved functionality compared to standard polyurethanes having high levels of hydrogen bonding. Thus, the materials disclosed herein are tough, are less susceptible to loss of toughness in the presence of water, and have improved elongation properties without disrupting the polymer backbone.

[0152] I. Polymer Chain

[0153] The present disclosure provides polymer chains comprising rings (also referred to herein as ring monomers, ring units, ring monomers, and rings). In some embodiments, the ring is positioned within the polymer chain (ie, is an intrachain loop). Figure 11Shown are exemplary polymer chains comprising a ring disclosed herein. The ring includes at least three ring members (i.e., a ring size with 3 or more atoms). The ring is connected to the polymer chain by the first joint and the second joint. The ring includes a weak bond and / or comprises a weak bridge of the weak bond, wherein the weak bond and / or the weak bridge are located in the ring between two atoms in the three or more atoms (i.e., the weak bond is located between one group of two ring members). In some embodiments, the weak bridge is located between the first joint and the second joint. In some embodiments, the weak bond is a weak covalent bond. The ring also includes at least one bond (i.e., the second bond) with a bond dissociation energy greater than 325kJ / mol between the groups of two ring members. In some embodiments, the ring includes multiple bonds between the groups of two ring members, and the bond dissociation energy of each of the multiple bonds is greater than the bond dissociation energy of the weak bond. In some embodiments, the multiple bonds each have a bond dissociation energy greater than 325kJ / mol. In certain embodiments, the multiple bonds are located between the first joint and the second joint. In some embodiments, a series of multiple keys are positioned between the first joint and the second joint so that the key of the series does not include weak bonds.Joint (also referred to as intrachain joint herein) connects polymer to the second key and / or multiple keys and / or bridge and / or weak bonds.In some embodiments, joint is flexible.In some embodiments, joint is rigid.In some embodiments, the first key (that is, weak bonds) has a bond dissociation energy less than 325kJ / mol.In some embodiments, described ring is positioned between two polymer chains as cross-linking unit.

[0154] about Figure 12 , provides another non-limiting example of a ring monomer. Figure 12 In an embodiment of the present invention, the ring is a thioctane ring having 8 ring members (i.e., a ring size of 8 atoms). The ring includes 7 carbon atoms connected in series between the first linker and the second linker (i.e., a plurality of bonds between groups of two ring members, each of the plurality of bonds having a bond dissociation energy greater than the bond dissociation energy of one or more weak bonds). The ring also includes a weak bridge comprising two weak carbon-sulfur bonds. The linker includes an acrylate functional group.

[0155] about Figures 13A-13D , Figure 12 Non-limiting examples of cyclic monomers are shown for incorporation and use in polymer chains. Figure 13A Shown Figure 12 Non-limiting examples of cyclic monomers that can be incorporated into the polymer chain as crosslinks ( Figure 13B ).like Figure 13C As shown in , tension applied to the polymer chain can induce strain in the ring. Figure 13DAs shown, the applied tension can selectively break the weak bonds of the ring at the weak bridges, while the multiple carbon-carbon bonds of the ring and the polymer chain remain intact, generating free radicals at the corresponding carbon and sulfur, thereby providing improved elongation and stress relaxation properties while maintaining the integrity of the polymer material.

[0156] The present disclosure provides a composition comprising a polymer chain, the polymer chain including a ring comprising three or more ring members, a first bond (i.e., weak bond) positioned between two ring members of the first group and having a bond dissociation energy less than 325kJ / mol, and a second bond positioned between two ring members of the second group and having a bond dissociation energy greater than the bond dissociation energy of the first bond. In some embodiments, the second bond has a bond dissociation energy greater than 325kJ / mol. In some embodiments, the ring includes a weak bridge, which includes the first bond. In some embodiments, the ring includes a substituted or unsubstituted cycloalkane, a substituted or unsubstituted heterocycle, a substituted or unsubstituted inorganic ring, a derivative thereof, or a combination thereof. In some embodiments, the ring size of the ring is 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or greater than 20 atoms (i.e., ring members). In some embodiments, the ring size is greater than 10, greater than 15, greater than 20, greater than 25, greater than 30, greater than 35, greater than 40, greater than 45, or greater than 50 atoms. In some embodiments, the ring comprises 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or greater than 20 ring members connected in series. In some embodiments, the ring comprises greater than 10, greater than 15, greater than 20, greater than 25, greater than 30, greater than 35, greater than 40, greater than 45, or greater than 50 ring members connected in series. In some embodiments, the ring comprises greater than 6, greater than 7, greater than 8, greater than 9, or greater than 10 ring members. In some embodiments, the ring comprises 10 to 20 ring members.

[0157] In some embodiments, the ring includes a weak bridge (i.e., a series of bonds including a weak bond) and a strong bridge (i.e., a series of bonds without a weak bridge), each of which is located between the first linker and the second linker. As a non-limiting example, Figure 12Monomers comprising a weak bridge (carbon-sulfur-carbon located between the first and second joints) and a strong bridge (7 carbons connected in series between the first joint and the second joint, and no weak bridge is present) are shown. In some embodiments, the weak bridge has the same number of atoms and / or the same number of bonds connected in series between the first and second joints as the strong bridge. In some embodiments, the weak bridge has a smaller number of atoms and / or a smaller number of bonds connected in series between the first and second joints than the strong bridge. In some embodiments, the weak bridge has 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or more than 15 bonds and / or atoms connected in series between the first and second joints than the strong bridge. As a non-limiting example, go to Figure 12 , the monomer shown has 2 bonds in the weak bridge connected in series between the first and second joints, and the strong bridge has 6 bonds connected in series between the first and second joints, so the weak bridge has 4 fewer bonds connected in series between the first and second joints than the strong bridge. In some embodiments, the size of each atom is roughly similar, and / or the size of each bond is roughly similar. In some embodiments, the strong bridge includes more than 4 bonds and / or atoms connected in series between the first joint and the second joint than the weak bridge. In some embodiments, the strong bridge includes more than 5, more than 6, more than 7, more than 8, more than 9, or more than 10 bonds and / or atoms connected in series between the first joint and the second joint than the weak bridge. In some embodiments, the expected or calculated linear length of the strong bridge is equal to the corresponding expected or calculated linear length of the weak bridge. In some embodiments, the expected or calculated linear length of the strong bridge is greater than the corresponding expected or calculated linear length of the weak bridge. In some embodiments, there is a ratio of expected or calculated linear lengths of weak bridges to the corresponding expected or calculated linear lengths of strong bridges, wherein the ratio is less than or equal to 1:1, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, or less than or equal to 1:10.

[0158] In some embodiments, the polymer chain includes a plurality of rings disclosed herein. In certain embodiments, the polymer chain includes 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of one or more rings and / or one or more ring monomers. In some embodiments, the polymer chain comprises greater than 10 wt%, greater than 20 wt%, greater than 30 wt%, greater than 40 wt%, greater than 50 wt%, greater than 60 wt%, greater than 70 wt% of one or more rings and / or one or more ring monomers. In some embodiments, the polymer chain comprises a ratio of the total number of bonds to one or more rings to the total number of bonds to the polymer chain, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10.

[0159] In some embodiments, polymer chain includes the first and second parts, and the first part of polymer chain is attached to the ring at the first joint, and the second part of polymer chain is attached to the ring at the second joint.In certain embodiments, weak bond is between the first joint and the second joint, and the ring includes a plurality of keys between the groups of two ring members, and the bond dissociation energy of each of the plurality of keys is greater than weak bond.In certain embodiments, the plurality of keys are connected in series and are arranged between the first joint and the second joint, and weak bond is not in the series connection of the plurality of keys (that is, strong bridge).In some embodiments, ring monomer is attached to the end of the first part of polymer chain and / or ring monomer is attached to the end of the second part of polymer chain.In some embodiments, ring monomer is attached to the main chain of the first part of polymer chain and / or ring monomer is attached to the main chain of the second part of polymer chain.

[0160] In some embodiments, the bond dissociation energy of the weak bond is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, or less than or equal to 150 kJ / mol. In some embodiments, the bond dissociation energy of the weak bond is 50 kJ / mol to 325 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In some embodiments, the weak bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In certain embodiments, the weak bond has a thermal decomposition temperature below 350°C. In some embodiments, the weak bond has a thermal decomposition temperature below the thermal decomposition temperature of the polymer chain. In some embodiments, the weak bond has a thermal decomposition temperature below the thermal decomposition temperature of the multiple bonds of the ring in which the weak bond is not present.

[0161] In some embodiments, the weak bond is a dynamic covalent bond. In some embodiments, the weak bridge comprises a dynamic covalent bond.

[0162] In some embodiments, the weak bond is selected from the group consisting of sulfur-sulfur bonds, oxygen-oxygen bonds, nitrogen-nitrogen bonds, silicon-sulfur bonds, silicon-silicon bonds, phosphorus-phosphorus bonds, oxygen-sulfur bonds, nitrogen-phosphorus bonds, carbon-phosphorus bonds, phosphorus-silicon bonds, carbon-sulfur bonds, nitrogen-oxygen bonds, and combinations thereof.

[0163] In some embodiments, a ring includes a plurality of bonds (e.g., covalent bonds) between groups of two ring members, each of the plurality of bonds having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak bond. As non-limiting examples, Figure 12 A ring containing six carbon-carbon bonds (ie, multiple bonds between groups of two ring members) is shown, with relatively high dissociation energies compared to the two weak carbon-sulfur bonds.

[0164] In some embodiments, the weak bond is attached to one or more stable molecular structures. In certain embodiments, the stable molecular structure is located at a joint. In some embodiments, the weak bond is attached to 1, 2, 3 or more stable molecular structures. In certain embodiments, each side of the weak bond is attached to at least one stable molecular structure. The free radical or ion formed after the stable molecular structure stable bond breaks. See: McMillen et al., Hydrocarbon Bond Dissociation Energies, Ann. Rev. Phys. Chem., 1982, 33: 493-532, which is incorporated herein by reference. The weak bond can be, for example, a carbon-carbon bond between two stable molecular structures. As a non-limiting example, the carbon-carbon bond of 1,1,2,2-tetraphenylethane has a bond dissociation energy of 247.3 ± 8.4 kJ / mol, while the carbon-carbon bond of ethane has a bond dissociation energy of 377.4 ± 0.8 kJ / mol. See: Luo, Yu-Ran "Handbook of Bond Dissociation Energies in Organic Compounds" CRC Press, 2002, which is incorporated herein by reference. In some embodiments, the weak bond is a carbon-carbon bond. As a non-limiting example, Figure 14A and Figure 14C Each of the carbon-carbon bonds described herein as the weak bond between the stable benzyl rings. In certain embodiments, the weak bond is a carbon-carbon bond, in which one or two carbon atoms are attached to one, two or more stable molecular structures. In some embodiments, the weak bond is a carbon-carbon bond, in which two carbon atoms are each attached to at least one stable molecular structure. In some embodiments, the stable structure is an aromatic ring. In certain embodiments, the stable structure includes benzene, naphthalene, anthracene, pyridine, quinoline, isoquinoline, pyrazine, quinoxaline, acridine, pyrimidine, quinazoline, pyridazine, cinnoline, phthalazine, 1,2,3-triazine, 1,2,4-triazine, s-triazine, furan, pyrrole, thiophene, imidazole, pyrazole, oxazole, isoxazole or thiazole.

[0165] In some embodiments, the weak bond is a nonpolar covalent bond or a polar covalent bond. In some embodiments, the weak bond is a plurality of hydrogen bonds (e.g., Figure 14F In certain embodiments, the weak bond is an ionic bond (e.g., Figure 14DIn some embodiments, the weak bond is an organometallic bond. Exemplary organometallic bonds have bond dissociation energies as described by Basch "Bond dissociation energies in organometallic compounds" Inorganica Chima Acta 252 (1996) 265-279, which is incorporated herein by reference. In some embodiments, the weak bond is a heterolytic bond (e.g., Figure 14B and Figure 14E Exemplary heterolytic bonds have bond dissociation energies as described in Kitagawa et al., "Structural dependence of heterolytic bond dissociation energy of σ carbon-carbon bonds in hydrocarbons," Journal of Physical Organic Chemistry, 11 (1998), 157-170, which is incorporated herein by reference.

[0166] In some embodiments, the weak bond (i.e., the first bond) has less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond strength in the polyethylene.

[0167] In some embodiments, the polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weaker bonds.

[0168] In certain embodiments, the bond dissociation energy of a weak bond is measured as a bond dissociation energy or a bond breakage energy.

[0169] In some embodiments, the ring includes a first linker, a second linker, and a weak bond between the first linker and the second linker (e.g., Figure 11 and Figure 12In some embodiments, the weak bond is a weak covalent bond. The weak covalent bond is weaker than the covalent bond of the polymer backbone. A non-limiting example of a polymer backbone is a polyacrylate, whose carbon-carbon bonds tend to have a bond dissociation energy of 340 kJ / mol to 360 kJ / mol. In some embodiments, the weak bond is thermally stable at room temperature and / or human body temperature (e.g., human oral temperature). In some embodiments, the ring comprising a weak bond or the weak bridge comprising a weak bond as described herein is located within a polymer chain (e.g., a polyacrylate chain).

[0170] In some embodiments, the polymer chains are hydrophobic.

[0171] In some embodiments, the polymer chain includes a ring comprising 3 or more ring members and a first bond (i.e., an activatable unit) between two ring members of the first group, wherein upon activation of the catalyst, the first bond is converted to a weak bond as disclosed herein. The resulting weak bond is between two atoms of the three or more atoms of the ring. For example, the activatable unit may be a unit in which a weak bond is not present, and after activation, the unit comprises a weak bond. In some embodiments, when activated by an activator (e.g., a catalyst), a reagent, and / or a reactant, the activatable unit is converted to a weak bond (i.e., activated) to form a cyclic monomer comprising a weak bond as disclosed herein. In some embodiments, the weak bond has a bond dissociation energy of less than 325 kJ / mol. Some non-limiting examples of activators include light energy (e.g., as non-limiting examples, ultraviolet light, two-photon absorption, visible light, x-rays, infrared light, and gamma rays), catalysts (e.g., as non-limiting examples, tin derivatives, bismuth derivatives, zinc derivatives, titanium derivatives, palladium, platinum, amines, The activating agents include, but are not limited to, alkali, Lewis bases, metal halide salts, organic salts, Lewis acids, protic acids, and iodonium salts), additional energy sources (e.g., by way of non-limiting example, heat, sound (i.e., acoustic energy), and electricity), and reagents that react with bonds (e.g., by way of non-limiting example, free radicals, ions, water, alcohols, amines, nucleophiles, electrophiles, oxidants, reducing agents, hydrogenating agents, acylating agents, chelating agents, electron donors, and electron acceptors), or combinations thereof. In some embodiments, two or more activating agents are used.

[0172] In certain embodiments, polymer chain includes organic polymer, inorganic polymer or hybrid polymer.In some embodiments, organic polymer is selected from polyethylene, polypropylene, polybutene, polyisoprene, polyacrylate, polymethacrylate, thioether-containing polymer, polyether, polyester, polyurethane, polyamide, polyepoxide, its copolymer, its mixture, its combination and derivative thereof.In some embodiments, organic polymer includes hydrogen bond system (for example, polyurethane and polyamide), and with the mixture or copolymer of organic polymer as described herein.In some embodiments, inorganic polymer is selected from polysilane, polysiloxane, polyphosphazene, its copolymer, its mixture, its combination and derivative thereof.Hybrid polymer (for example, organic-inorganic polymer) can include any organic polymer and any inorganic polymer, its copolymer, its mixture and derivative thereof.In some embodiments, polymer chain is basically composed of ring monomer and organic polymer, inorganic polymer, hybrid polymer or its any combination.

[0173] II. Polymer Materials

[0174] i. Ring monomer

[0175] The present disclosure provides a polymer material comprising a polymer chain disclosed herein. The present disclosure provides a polymer material comprising: a ring comprising three or more ring members; a first bond (i.e., a weak bond) located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; and a second bond located between a second set of two ring members and having a bond dissociation energy greater than the weak bond. In some embodiments, the second bond has a bond dissociation energy greater than 325 kJ / mol.

[0176] In some embodiments, the polymeric material comprises: a ring comprising three or more ring members; a first bond located between two ring members of the first group, wherein upon activation of the catalyst, the first bond is convertible into a bond having a bond dissociation energy of less than 325 kJ / mol (also referred to herein as an activatable unit); and a second bond located between two ring members of the second group and having a bond dissociation energy greater than that of a weak bond. In some embodiments, the second bond has a bond dissociation energy greater than 325 kJ / mol. The resulting weak bond is located between two of the three or more members of the ring. In certain embodiments, the polymeric material further comprises a catalyst.

[0177] In some embodiments, the polymeric material comprises a plurality of rings disclosed herein. In certain embodiments, the polymeric material comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of one or more rings and / or ring monomers disclosed herein. In some embodiments, the polymeric material includes a ratio of the total number of bonds of the ring to the total number of bonds of the polymer backbone of the polymeric material, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10.

[0178] In some embodiments, the polymeric material includes greater than 0.1 wt%, greater than 0.5 wt%, greater than 1 wt%, greater than 2 wt%, greater than 3 wt%, greater than 4 wt%, greater than 5 wt%, greater than 6 wt%, greater than 7 wt%, greater than 8 wt%, greater than 9 wt%, greater than 10 wt%, greater than 15 wt%, greater than 20 wt%, greater than 25 wt%, greater than 30 wt%, greater than 35 wt%, greater than 40 wt%, greater than 45 wt%, greater than 50 wt%, greater than 60 wt%, or greater than 70 wt% of one or more rings.

[0179] Conventional polymeric materials (e.g., polyurethanes) have hydrogen bonds with bond strengths ("bond dissociation energies") that are typically in the range of 8 to 30 kJ / mol. Hydrogen bonds are dynamic at room temperature (i.e., they can be broken and reformed). In some embodiments, the weak bonds described further herein have bond dissociation energies of 10 to 340 kJ / mol. In some embodiments, the weak bonds described further herein have bond dissociation energies of 60 to 200 kJ / mol. In some embodiments, the weak bonds described further herein are dynamic bonds. As used herein, the terms "bond strength" and "bond dissociation energy" refer to bond dissociation energies. Other tools can be used to measure bond strength, including using heterolytic bond breakage energies or molecular modeling to estimate bond dissociation energies. Exemplary bond dissociation energies are Figure 5 shown.

[0180] In some embodiments, the bond dissociation energy of the weak bond is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, or less than or equal to 150 kJ / mol. In some embodiments, the bond dissociation energy of the weak bond is 50 kJ / mol to 325 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In certain embodiments, the weak bond has a thermal decomposition temperature below 350°C. In some embodiments, the weak bond has a thermal decomposition temperature below the thermal decomposition of the polymer chain. In some embodiments, the weak bond has a thermal decomposition temperature below the thermal decomposition of the polymer backbone. In some embodiments, the thermal decomposition temperature of the weak bond is lower than the thermal decomposition of a plurality of bonds between the group of two ring members, each of the plurality of bonds having a bond dissociation energy of 325 kJ / mol or greater.

[0181] In some embodiments, polymeric material includes multiple rings, and each ring includes a weak bond disclosed herein. In some embodiments, polymeric material includes multiple ring units (that is, loops) arranged in the polymer chain, to become an intrachain loop. In certain embodiments, polymeric material includes multiple ring units, to be arranged to be cross-linked between the first polymer chain and the second polymer chain. In some embodiments, multiple ring units are dispersed in the whole polymeric material. In some embodiments, multiple rings are each attached to the first polymer chain (for example, using the first joint) at the first end, and are attached to the second polymer chain (such as, using the second joint) at the second end.

[0182] In some embodiments, the catalyst acts on the polymer material to produce a weak bond and / or a weak bridge comprising a weak bond, wherein the weak bridge and / or the weak bond is in a ring as described herein. As a non-limiting example, the polymer material may be composed of relatively strong bonds (e.g., there is no weak bond, such as a weak covalent bond), but after the addition of the catalyst, a weak bond (e.g., a weak covalent bond) is present. As a non-limiting example, the polymer material may include a ring comprising an ester located between the first joint and the second joint, the ester being an extremely stable bond; after the addition of water and a weak acid (i.e., in this case, water is a reagent and the acid is a catalyst), the ester is more effectively broken (i.e., hydrolyzed) when placed under pressure; therefore, the ester becomes a weak bond in the presence of water and acid, thereby forming a ring comprising a weak bond between the first joint and the second joint. The bond strength of disulfide bonds and esters can be reduced in the presence of metal ions and / or Lewis acids and / or by changes in pH. In some embodiments, the weak bond comprises a disulfide or an ester, and the catalyst comprises a metal ion, a Lewis acid, a pH change, or any combination thereof. In this manner, a polymeric material can be formed without weak bonds, but after addition of the catalyst, the polymeric material includes weak bonds (e.g., weak covalent bonds). In some embodiments, the catalyst selectively reduces the bond dissociation energy of the activatable bond and / or the weak bridge, thereby forming a weak bond and / or a weak bridge comprising a weak bond, respectively, in the presence of the catalyst.

[0183] In some embodiments, the catalyst selectively reorganizes the bond. As a non-limiting example, a polymer material comprising a ring containing a disulfide bond (i.e., a dynamic covalent bond) can be activated by a photoinitiator (i.e., a catalyst) under stress. The free radicals from the photoinitiator can destroy the disulfide bond, and then reorganize and reform a new disulfide bond. In this way, stress is released from the system only by releasing stress from the disulfide bond. This allows selective bond rupture (e.g., during the elongation period during the application of tension), by preventing the bond rupture of multiple bonds between the groups of the polymer backbone or ring members to maintain the strength of the polymer material, wherein the bond dissociation energy of each of the multiple bonds is greater than the bond dissociation energy of the weak bond. In some embodiments, the catalyst disclosed herein rearranges the weak covalent bond in one or more rings. Another non-limiting example is to add an intrachain peroxide in combination with a ring comprising a disulfide, which produces a rapid reorganization of the polymer chain network. In this non-limiting example, when the intrachain peroxide bond breaks (the concentration of the peroxide is relatively low relative to the disulfide bond concentration), the peroxy radical catalyzes the disulfide bond cleavage reaction. Thus, in this non-limiting example, the breaking of one weak bond (the peroxide bond) results in the breaking of multiple bonds (e.g., disulfide bonds) which, in this non-limiting example, can reform into stable covalent bonds when the stress is removed or when all free radicals are removed, reacted, or trapped.

[0184] In some embodiments, the catalyst selectively reduces the bond dissociation energy of the activatable unit and / or the bond comprising the weak bridge of the activatable unit, thereby forming a weak bond and / or a weak bridge comprising a weak bond, respectively, in the presence of the catalyst.

[0185] In some embodiments, polymeric material also includes catalyst (also referred to as activator in this article). In some embodiments, polymeric material is formed by the resin comprising catalyst. In some embodiments, the resin comprising catalyst includes intrachain catalyst. The non-limiting example of intrachain catalyst is intrachain peroxide as described above. For example, intrachain peroxide can be broken in the presence of disulfide bond, catalyzing disulfide bond cleavage reaction, and when stress is removed or when all free radicals are removed, reacted or captured, disulfide bond cleavage reaction can reform stable covalent bond. Peroxide can also be activated, for example, by heat and light. In some embodiments, catalyst (for example, peroxide) is freely diffused in the system. In some embodiments, after forming the polymeric material comprising one or more loops, catalyst (for example, peroxide) is added to the polymeric material.

[0186] In some embodiments, the polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weaker bonds. In some embodiments, the polymer chain comprises a first polymer chain attached to the ring and a second polymer chain attached to the ring, wherein the first polymer chain comprises a backbone, wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak bond. In some embodiments, the second polymer chain comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak bonds.

[0187] In some embodiments, the first polymer chain, the second polymer chain, or each of the first polymer chain and the second polymer comprises a backbone wherein all covalent bonds in the backbone have a bond dissociation energy greater than 280 kJ / mol or greater than 300 kJ / mol.

[0188] In some embodiments, polymeric material also comprises strong cross-linking unit.Comprise strong cross-linking unit and comprise the polymeric material of weak key ring both can have the advantageous property of increasing intensity, retain weak key simultaneously, this weak key can selectively break and / or stretch when applying stress.In certain embodiments, each key of strong cross-linking unit has the bond dissociation energy being greater than or equal to 275kJ / mol.In some embodiments, each key of strong cross-linking unit has the bond dissociation energy being greater than or equal to 300kJ / mol.

[0189] In some embodiments, the polymeric material comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of one or more rings and / or one or more ring monomers. In some embodiments, the polymeric material comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, 0.1 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.1 wt%, or less than 0.01 wt% of weak bridges and / or weak bonds. In some embodiments, the polymeric material comprises greater than 0.1 wt% of weak bonds. In some embodiments, the polymeric material comprises greater than 50 wt% weak bonds. The weight percentage of weak bridges and / or weak bonds can be calculated or measured by the weight percentage of weak bridges and / or weak bonds. As a non-limiting example, the SS of a disulfide bond acts as a weak bond; thus, a polymeric material having less than 1 wt% of SS units in a ring containing a weak bond thus has less than 1 wt% weak bonds.

[0190] In some embodiments, the polymeric material comprises a ratio of the total number of bonds of weak bridges and / or weak bonds to the total number of bonds of the polymer chain, and the ratio is 1:2500 to 1:10, 1:2000 to 1:10, 1:1500 to 1:10, 1:1000 to 1:10, 1:750 to 1:1, 1:500 to 1:10, 1:400 to 1:10, 1:300 to 1:10, 1:250 to 1:10, 1:200 to 1:10, 1:100 to 1:10, 1:50 to 1:10, 1:40 to 1:10, 1:30 to 1:10, or 1:20 to 1:10. In some embodiments, the ratio of the total number of weak bridges and / or weak bonds to the total number of bonds in the polymer chain is 1:1000 to 1:100, 1:900 to 1:150, 1:800 to 1:200, or 1:750 to 1:250.

[0191] Some polymeric materials traditionally used to make appliances (e.g., orthodontic appliances) include high levels of hydrogen bonding units (e.g., urethanes, ureas, amides, hydroxyls, amines, carbonyl-based acids, phosphorus-based acids, sulfur-based acids, poly(ethylene glycol) ethers, or derivatives thereof). In some embodiments, the polymeric materials disclosed herein contain less than 10 wt%, less than 9 wt%, less than 8 wt%, less than 7 wt%, less than 6 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, or less than 1 wt% hydrogen bonding units. The percentage of hydrogen bonding units can be calculated or measured by the weight percentage of hydrogen bonding groups. As a non-limiting example, the NHCO of an amide bond acts as both a hydrogen donor and a hydrogen acceptor; therefore, a polymeric material having less than 10 wt% NHCO units (without other types of hydrogen bonding units) has less than 10 wt% hydrogen bonding units. Alternatively, in some embodiments, the value of the wt% hydrogen bonding units can be determined by performing a titration to obtain the number of hydrogen bonding groups. In some embodiments, the polymeric material contains less than 5 wt% hydrogen bonding units. In some embodiments, the polymer material contains less than 2 wt% hydrogen bonding units. In some embodiments, the polymer material does not substantially include hydrogen bonding units. A low amount of hydrogen bonding units in the polymer material can result in the polymer material having a relatively low level of water absorption because the presence of hydrogen bonding units promotes such absorption. Advantageously, resins with reduced hydrogen bonding groups tend to have lower viscosities than base polymers with the same hydrogen bonding groups, which can improve the practicality of using a stereolithography 3D printer as a non-limiting example.

[0192] In some embodiments, the polymeric materials described herein have a low level of water absorption. This low level of water absorption is advantageous for the polymeric materials described herein, orthodontic devices, or other applications in which water absorption is detrimental. Water absorption occurs when the polymeric material is exposed to a humid environment (e.g., the mouth of a patient using an orthodontic appliance formed from a polymeric material). Traditional polymeric materials with high levels of hydrogen bonding are advantageous for water absorption because water is attracted to hydrogen bonding groups; water molecules are also attracted to polar atoms. In some embodiments, the polymeric materials disclosed herein have weak bonds with low polarity atoms or non-polar atoms, thereby minimizing water absorption. In certain embodiments, the polymeric material includes polar atoms in weak covalent bonds, but the bonds are minimally disrupted to not disrupted by water, thereby maintaining the integrity of the polymeric material. When water absorption reaches a threshold value (typically greater than 22 wt%), the performance of the polymeric material degrades. It is preferred herein that the polymeric material have a low level of water absorption. In some embodiments, the polymeric material comprises a water absorption of less than 25 wt%, less than 20 wt%, less than 15 wt%, less than 10 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.5 wt%, less than 0.25 wt%, or less than 0.1 wt%. In some embodiments, the water absorption is measured after 24 hours in a humid environment at 37°C. In some embodiments, the water absorption is measured using a sample no thicker than 1 mm. In certain embodiments, the water absorption is measured using a sample 1 mm thick. In some embodiments, the polymeric material is hydrophobic.

[0193] In some embodiments, it is desirable to form a hydrophilic or hygroscopic material that retains toughness even after absorbing water. As a non-limiting example, a hydrogel incorporating one or more loop units comprising one or more weak bonds as described herein will provide a hydrogel material of toughness. Other materials that traditionally rely on hydrogen bonds to provide toughness can benefit by incorporating loop units comprising weak bridges and / or weak bonds as described herein. In some cases, the absorption of water in the hydrogel can produce stress on the cross-linked polymer matrix, thereby causing the covalent bonds to break and the polymer itself to tear. By introducing loop units with weak bridges as described herein, the hydrogel absorbs more water and can alleviate the stress of the increased water content by breaking weak bonds without compromising the integrity of the polymer network. Using the currently disclosed rings and related materials, it is easy to design materials that absorb oil, solvents, water or other compounds without losing material integrity. Materials comprising one or more ring units can absorb greater than 10%, greater than 50%, greater than 100%, greater than 200%, greater than 300%, greater than 500%, or greater than 1000% of their initial weight in water, aqueous solutions, oils, salts, target molecules, bioactive molecules, drugs, dyes, and / or other compounds without breaking down. In some embodiments, once absorbed, the absorbed material can be used as a sustained-release device. In some embodiments, once absorbed, the absorbed material is considered to be sequestered.

[0194] In certain embodiments, the polymeric material comprises a polymer chain comprising a plurality of monomers, each monomer being linked by a backbone covalent bond having a bond dissociation energy that is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of a weak bond.

[0195] In some embodiments, the ring monomer is attached to the polymer chain via a first linker comprising a covalent bond. In some embodiments, the ring monomer is attached to the polymer chain via a second linker comprising a covalent bond. In some embodiments, each of the first linker and the second linker attaches the polymer chain to the ring monomer via a covalent bond.

[0196] In some embodiments, the weak bonds are dynamic covalent bonds. In certain embodiments of the polymeric material, at least 1%, at least 2%, at least 3%, at least 4%, at least 5%, at least 10%, at least 20%, at least 30%, at least 40%, or at least 50% of the weak bonds are dynamic covalent bonds. In some embodiments, the dynamic covalent bonds are free radical dynamic covalent bonds (i.e., weak covalent bonds that break to form free radicals that can combine with other free radicals to reform or form new bonds).

[0197] A polymer material having weak bonds and / or weak bridges comprising weak bonds has bonds in the polymer material that are weaker than the main chain of the polymer material, so when the material is manipulated (e.g., pulled), the weak bonds break before other bonds present in the polymer main chain or ring (e.g., multiple bonds connected in series, each bond is between a group of two ring members, and the bond dissociation energy of each bond is greater than the weak bond) break, thereby relieving stress and maintaining the strength of the polymer main chain. Main chain breakage in the polymer material results in rapid rupture, so the incorporation of rings comprising weak bonds and / or weak bridges comprising weak bonds prevents breakage. In some embodiments, the stress applied to the polymer material breaks the weak bonds before breaking the covalent bonds of the polymer chain or the multiple bonds connected in series (see, e.g., Figure 8D , wherein the carbon-sulfur bond (i.e., the weak bond) breaks upon application of tension, while the polymer chain and the multiple bonds connected in series (i.e., the 7 carbon atoms located between the two aromatic rings) remain intact). Another non-limiting example of the advantage of a ring monomer containing a weak bond is how it affects the property of elongation at break. Another property affected by the presence of a ring containing a weak bond includes yield strength (i.e., the addition of a ring containing a weak bond will reduce the yield strength compared to a strongly crosslinked material when the molar amounts of the two are the same). In some embodiments, increasing the concentration of the ring containing a weak bond increases the yield strength, but potentially maintains the elongation at break value.

[0198] In some embodiments, the ring comprising a weak bond can be used for organic, inorganic or hybrid systems. In certain embodiments, polymer includes organic polymer, inorganic polymer or hybrid polymer. In some embodiments, organic polymer is selected from polyethylene, polypropylene, polybutene, polyisoprene, polyacrylate, polymethacrylate, thioether-containing polymer, polyether, polyester, its copolymer, its mixture, its combination and derivative thereof. In some embodiments, organic polymer includes hydrogen bond system (for example, polyurethane and polyamide), and with the mixture or copolymer of organic polymer as described herein. In some embodiments, inorganic polymer is selected from polysilane, polysiloxane, polyphosphazene, its copolymer, its mixture, its combination and derivative thereof. Hybrid polymer (for example, organic-inorganic polymer) can include any organic polymer and any inorganic polymer, its copolymer, its mixture and derivative thereof.

[0199] C. Properties of polymer materials

[0200] The specific composition, synthesis, formulation and description of any material, device, system and components thereof disclosed herein can be readily varied depending on the intended application. Specifically, weak crosslinks, strong crosslinks, polymer chains and ring monomers can be used alone or in combination with any of the disclosures described herein.

[0201] The polymeric materials disclosed herein have properties that are advantageous for a variety of applications and the production of various devices. As a non-limiting example, the polymeric materials described herein can be used to produce orthodontic devices, such as aligners. Orthodontic devices require toughness and elasticity to move a patient's teeth while maintaining durability in use. In some embodiments, the polymeric materials have a high glass transition temperature, low creep, and low stress relaxation.

[0202] In the embodiments described herein, the polymeric material has a property that is measured after the material is placed in an aqueous environment at 37° C. for 24 hours. For example, the property value of the polymeric material can be determined by using the following method:

[0203] Stress relaxation properties can be evaluated in three-point bending according to ASTM D790 using a TA Instruments RSA-G2 instrument. Stress relaxation can be measured at 30°C immersed in water and reported as the residual load after 24 hours or as a percentage (%) of the initial load.

[0204] Storage modulus can be measured at 37°C and reported in MPa;

[0205] T of cured polymer material g It can be evaluated using dynamic mechanical analysis (DMA) and is presented herein as tan δ peak when run at 1 Hz with a temperature ramp of 2°C / min;

[0206] Tensile modulus, tensile strength, elongation at yield and elongation at break can be evaluated according to ISO 527-25B;

[0207] Tensile strength at yield, elongation at break, tensile strength, and Young's modulus can be evaluated according to ASTM D1708; and

[0208] The residual bending stress relaxation ("residual bending stress") after 24 hours in a humid environment at 37°C can be evaluated according to ASTM E328. Other methods can be used to characterize the materials described herein, and the above methods provide exemplary methods. For a given application, the selected material characterization method, the comparison of a polymer system without crosslinking, with strong crosslinking of similar length and flexibility and with weak covalent crosslinking will help determine whether the use of weak covalent crosslinking improves the performance of interest. For a given application, the selected material characterization method, the comparison of a polymer system with acyclic monomers and with cyclic monomers will help determine whether the properties of interest are improved by using one or more rings containing weak bonds. For some preferred comparisons, a material with one or more cyclic monomers containing weak bonds is compared with a comparable material with one or more cyclic monomers containing a substituted bond that replaces the weak bond, wherein the bond dissociation energy of the substituted bond is greater than the weak bond. In some embodiments, the bond dissociation energy of the substituted bond is equal to, similar to, or greater than the bond dissociation energy of the polymer chain backbone and / or the polymer network. In some embodiments, the concentration of the one or more monomers containing the substituted bond is the same as the concentration of the one or more monomers containing the weak bond.

[0209] In an embodiment, the polymeric material is characterized by a tensile stress-strain curve that shows a yield point, after which the test sample continues to elongate, but the load does not increase. This yield point behavior typically occurs "near" the glass transition temperature, where the material is between a glassy and rubbery state, and can be characterized as having viscoelastic behavior. In some embodiments, viscoelastic behavior is observed in the temperature range of 20°C to 40°C. The yield stress is determined at the yield point. In some embodiments, the yield point is after the elastic region where the slope of the stress-strain curve is constant or nearly constant. In some embodiments, the modulus is determined from the initial slope of the stress-strain curve, or as the secant modulus at 1% strain (e.g., when the stress-strain curve does not have a linear portion). The yield elongation is determined by the strain at the yield point. When the yield point occurs at the maximum stress, the ultimate tensile strength is less than the yield strength. For tensile test specimens, the strain is defined by ln(l / l0), which at small strains (e.g., less than about 10%) can be approximated as (l-l0) / l0, while the elongation is l / l0, where l is the gauge length after a certain deformation and l0 is the initial gauge length. Mechanical properties can depend on the temperature at which they are measured. The test temperature may be lower than the expected use temperature of the dental instrument, e.g., 35°C to 40°C. In some embodiments, the test temperature is 23±2°C. For some applications, the test temperature is above 40°C. For some applications, the test temperature is below 23°C.

[0210] In some embodiments, the polymeric material is characterized by one or more of the following: a tensile modulus greater than or equal to 100 MPa after being placed in an aqueous environment at 37°C for 24 hours; a tensile strength at yield greater than or equal to 5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a storage modulus greater than or equal to 300 MPa after being placed in an aqueous environment at 37°C for 24 hours; a residual flexural stress after 24 hours ("residual stress") greater than or equal to 1.5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a hardness of 60 Shore A to 85 Shore D after being placed in an aqueous environment at 37°C for 24 hours; and an elongation at break greater than or equal to 15% before and / or after being placed in an aqueous environment at 37°C for 24 hours.

[0211] In some embodiments, the polymeric material is characterized by a tensile modulus of 100 MPa to 3000 MPa, 100 MPa to 2500 MPa, 100 MPa to 2000 MPa, 500 MPa to 3000 MPa, 500 MPa to 2500 MPa, 500 MPa to 2000 MPa, 750 MPa to 3000 MPa, 750 MPa to 2500 MPa, or 750 MPa to 2000 MPa after testing in a humid environment at 37° C. for 24 hours. In some preferred embodiments, the polymeric material has a tensile modulus greater than 500 MPa after 24 hours in a humid environment at 37° C. In some preferred embodiments, the polymeric material is characterized by a tensile modulus greater than or equal to 800 MPa after 24 hours in a humid environment at 37° C.

[0212] In some embodiments, the polymeric material has a tensile strength at yield of 1 MPa to 100 MPa, 5 MPa to 85 MPa, 10 MPa to 75 MPa, 15 MPa to 65 MPa, 20 MPa to 55 MPa, or 25 MPa to 45 MPa. In a preferred embodiment, the polymeric material has a tensile strength at yield of 30 MPa to 60 MPa. In some embodiments, the polymeric material is characterized in that the tensile strength at yield is greater than or equal to 0.1 MPa, greater than or equal to 0.5 MPa, greater than or equal to 1 MPa, greater than or equal to 10 MPa, greater than or equal to 30 MPa, greater than or equal to 40 MPa, greater than or equal to 50 MPa, greater than or equal to 60 MPa, greater than or equal to 70 MPa, greater than or equal to 80 MPa, greater than or equal to 90 MPa, or greater than or equal to 100 MPa. In a preferred embodiment, the polymeric material is characterized in that the tensile strength at yield is greater than or equal to 30 MPa.

[0213] In some embodiments, the polymeric material is characterized by a storage modulus of 0.1 MPa to 4000 MPa, 50 MPa to 2750 MPa, 100 MPa to 2500 MPa, 200 MPa to 2250 MPa, 300 MPa to 3000 MPa, 500 MPa to 3000 MPa, 750 MPa to 3000 MPa, or 1000 MPa to 3000 MPa after 24 hours in a humid environment at 37° C. In preferred embodiments, the polymeric material is characterized by a storage modulus of 0.1 MPa to 4000 MPa, a storage modulus of 300 MPa to 3000 MPa, or a storage modulus of 750 MPa to 3000 MPa after 24 hours in a humid environment at 37° C.

[0214] It is advantageous for the polymeric material to have a residual bending stress of 5% or greater after testing in a humid environment at 37°C for 24 hours. In some embodiments, the residual bending stress is 5% or greater, 10% or greater, 15% or greater, 20% or greater, 25% or greater, 30% or greater, 35% or greater, 40% or greater, 50% or greater, 60% or greater, or 70% or greater. In some embodiments, the polymeric material is characterized in that the residual bending stress is greater than 10% when tested in a humid environment at 37°C for 24 hours. In some preferred embodiments, the polymeric material is characterized in that the residual bending stress is greater than 20% when tested in a humid environment at 37°C for 24 hours. In some more preferred embodiments, the polymeric material is characterized in that the residual bending stress is greater than 25% when tested in a humid environment at 37°C for 24 hours. In some embodiments, the polymeric material is characterized in that the residual bending stress after 24 hours at 37° C. in a humid environment is 5% to 50%, 10% to 50%, 15% to 50%, 20% to 50%, 25% to 50%, or 30% to 50% of the initial load. In some embodiments, the polymeric material is characterized in that the residual bending stress after 24 hours at 37° C. in a humid environment is 5% to 100%, 10% to 100%, 15% to 100%, 20% to 100%, 25% to 100%, 30% to 100%, 40% to 100%, 50% to 100%, 60% to 100%, 70% to 100%, 80% to 100%, or 90% to 100% of the initial load. In some preferred embodiments, the polymeric material is characterized in that the residual bending stress after 24 hours at 37° C. in a humid environment is 20% to 45% of the initial load. In some preferred embodiments, the polymeric material is characterized by a residual bending stress greater than 50% of the initial load after 24 hours in a humid environment at 37°C.

[0215] In some embodiments, the polymeric material is characterized by a residual bending stress of 0.01 MPa to 15 MPa, 0.05 MPa to 15 MPa, 0.1 MPa to 15 MPa, 0.5 MPa to 15 MPa, 1 MPa to 15 MPa, 2 MPa to 15 MPa, 3 MPa to 15 MPa, 4 MPa to 15 MPa, 5 MPa to 15 MPa, or 10 MPa to 15 MPa after 24 hours in a humid environment at 37° C. In some preferred embodiments, the polymeric material is characterized by a residual bending stress of 2 MPa to 15 MPa after 24 hours in a humid environment at 37° C. In some embodiments, the polymeric material is characterized by a residual bending stress of greater than or equal to 0.1 MPa, greater than or equal to 0.5 MPa, greater than or equal to 1 MPa, greater than or equal to 1.5 MPa, greater than or equal to 2 MPa, greater than or equal to 2.5 MPa, greater than or equal to 3 MPa, greater than or equal to 4 MPa, greater than or equal to 5 MPa, greater than or equal to 6 MPa, greater than or equal to 7 MPa, greater than or equal to 8 MPa, greater than or equal to 9 MPa, greater than or equal to 10 MPa, or greater than or equal to 15 MPa after 24 hours in a humid environment at 37° C. In some preferred embodiments, the polymeric material is characterized by a residual bending stress of greater than or equal to 1.5 MPa after 24 hours in a humid environment at 37° C.

[0216] In some embodiments, the polymeric material has a stress relaxation measurement determined by ASTM D790, with a deformation of 5% in a three-point bending test. In some embodiments, stress relaxation can be measured by monitoring the time-dependent stress generated by the stable strain. The degree of stress relaxation can also depend on temperature, relative humidity and other applicable conditions (e.g., the presence of water). In an embodiment, the test conditions for stress relaxation are a temperature of 37±2°C at 100% relative humidity or a temperature of 37±2°C in water. Stress relaxation performance can be evaluated using the RSA-G2 instrument of TA Instruments with a 3-point bending, 5% strain method. Stress relaxation is typically measured at 37°C and 100% relative humidity and reported as a residual load after 2 hours, expressed as a percentage (%) of the initial load or MPa. In some embodiments, the residual stress of the polymeric material is greater than or equal to 5% of the initial load. In some embodiments, the polymeric material is characterized in that the residual stress is 5% to 45% of the initial load. In some aspects, the polymeric material is characterized in that the residual stress is 20% to 45% of the initial load. In certain embodiments, the polymeric material is characterized by a residual stress of greater than or equal to 20% or greater than or equal to 35% of the initial load. In some embodiments, the stress relaxation of the polymeric material measured in 30°C water for 24 hours is greater than 10% of the initial stress. In some embodiments, the stress relaxation of the polymeric material measured in 30°C water for 24 hours is greater than 15%, greater than 20%, greater than 25%, greater than 30%, greater than 35%, greater than 40%, greater than 45%, or greater than 50% of the initial stress. In some embodiments, the residual stress of the polymeric material is greater than or equal to 0.01 MPa. In certain embodiments, the polymeric material is characterized by a residual stress of 0.01 MPa to 15 MPa. In certain aspects, the polymeric material is characterized by a residual stress of 2 MPa to 15 MPa.

[0217] In some embodiments, the polymeric material is characterized by a residual stress of 5% to 85% of the initial load, such as 5% to 45%, 15% to 85%, or 20% to 45% of the initial load. In some embodiments, the polymeric material is characterized by a residual stress of 0.01 MPa to 15 MPa, such as 2 MPa to 15 MPa. In some embodiments, the polymeric material is characterized by a residual stress greater than or equal to 20% of the initial load.

[0218] In certain embodiments, it is advantageous that the polymer material has a high residual bending stress, thereby forming a relatively rigid material. In some applications related to the use of hard materials (e.g., aerospace engineering, medical implants), the polymer material disclosed herein will be advantageous because conventional 3D printers can be used to form these polymer materials with desired properties. In some embodiments, the polymer material has a residual bending modulus of 50MPa or greater, 60MPa or greater, 70MPa or greater, 80MPa or greater, 90MPa or greater, 100MPa or greater, 125MPa or greater, or 150MPa or greater. In some embodiments, the residual bending modulus is measured after 24 hours in a humid environment at a use temperature. In certain embodiments, the use temperature is 37°C.

[0219] In certain other embodiments, it is advantageous for the polymeric material to have a relatively low residual bending stress, thereby forming a material that is not overly hard. In some embodiments, the polymeric material has a residual bending stress of 80 MPa or less, 70 MPa or less, 60 MPa or less, 55 MPa or less, 50 MPa or less, or 45 MPa or less. In some embodiments, the residual bending stress is measured after 24 hours in a humid environment at the use temperature. In some embodiments, the use temperature is 37°C. In some embodiments, the polymeric material is characterized in that, after testing in a humid environment at 37°C for 24 hours, the residual stress is 0.01 MPa to 15 MPa, or the residual stress is 2 MPa to 15 MPa.

[0220] In some embodiments, the polymer material will have residual bending stress after use for a period of time. As a non-limiting example, an orthodontic appliance (e.g., an aligner) can be formed of a polymer material with high bending stress, but after the appliance is applied to the patient's teeth, the bending stress can be significantly and quickly reduced (e.g., within a few minutes). This reduction in bending stress can follow an exponential decline curve, leading to an asymptote during the expected life of the appliance (e.g., for orthodontic appliances, such as aligners, over the course of several weeks). The orthodontic appliance may have an initial discomfort period, which decreases as the residual bending stress decreases after use for a period of time. In some embodiments, the polymer material has a residual bending stress of 90 MPa or less, 85 MPa or less, 80 MPa or less, 75 MPa or less, 70 MPa or less, 65 MPa or less, 60 MPa or less, 55 MPa or less, or 50 MPa or less after use for a period of time. In a preferred embodiment, the polymer material has a residual bending stress of 80 MPa or less after use for a period of time. In some embodiments, the period of use is 1 minute, 5 minutes, 10 minutes, 30 minutes, 1 hour, or 24 hours. As a non-limiting example, an aligner comprised of a polymeric material placed on a patient's teeth, removed after 10 minutes, and having a bending stress of 70 MPa would have a polymeric material characterized by a residual bending stress of 70 MPa after a period of use, wherein the period of time is 10 minutes.

[0221] In some embodiments, the polymeric material is characterized in that the elongation at break is greater than 10%, the elongation at break is greater than 20%, the elongation at break is greater than 30%, the elongation at break is 5% to 250%, the elongation at break is 20% to 250%, or the elongation at break value is 40% to 250%. In certain embodiments, the elongation at break is measured under dry conditions (e.g., a dry environment). In some embodiments, the polymeric material is characterized in that, after testing in a humid environment at 37°C for 24 hours, the elongation at break is greater than 10%, the elongation at break is greater than 20%, the elongation at break is greater than 30%, the elongation at break is 5% to 250%, the elongation at break is 20% to 250%, or the elongation at break value is 40% to 250%. In some embodiments, the polymeric material is characterized by an elongation at break greater than 10%, an elongation at break greater than 20%, an elongation at break greater than 30%, an elongation at break between 5% and 250%, an elongation at break between 20% and 250%, or an elongation at break value between 40% and 250%, after testing in a dry environment and in a humid environment at 37°C for 24 hours.

[0222] In some embodiments, the polymeric material has an elongation at yield of greater than 4%, greater than 5%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15%. In some embodiments, the polymeric material has an elongation at yield of 4% to 10% or 5% to 15%. In certain embodiments, the elongation at yield is measured under dry conditions (e.g., dry environment). In some embodiments, the polymeric material has an elongation at yield of greater than 4%, greater than 5%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15% after being tested in a humid environment at 37°C for 24 hours. In some embodiments, the polymeric material has an elongation at yield of 4% to 10% or 5% to 15% after being tested in a humid environment at 37°C for 24 hours. In some embodiments, the polymeric material has an elongation at yield of greater than 4%, greater than 5%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15% after testing in a dry environment and in a humid environment at 37° C. for 24 hours. In some embodiments, the polymeric material has an elongation at yield of 4% to 10% or 5% to 15% after testing in a dry environment and in a humid environment at 37° C. for 24 hours.

[0223] In some embodiments, the polymeric material has at least one glass transition temperature (T gIn a preferred embodiment, the polymeric material has at least one glass transition temperature greater than 60°C. In a more preferred embodiment, the polymeric material has at least one glass transition temperature greater than 75°C. In some embodiments, the at least one glass transition temperature is from 0°C to 200°C, 0°C to 140°C, 0°C to 20°C, 20°C to 40°C, 40°C to 60°C, 60°C to 80°C, 80°C to 100°C, 100°C to 120°C, 120°C to 140°C, 140°C to 160°C, 160°C to 180°C, 180°C to 200°C, 0°C to 35°C, 35°C to 65°C, 65°C to 100°C, 0°C to 50°C, or 50°C to 100°C. In some embodiments, the polymeric material has at least one glass transition temperature of 0°C to 10°C, 10°C to 20°C, 20°C to 30°C, 30°C to 40°C, 40°C to 50°C, 50°C to 60°C, 60°C to 70°C, 70°C to 80°C, or 80°C to 90°C. In some embodiments, the polymeric material has at least one glass transition temperature of -100°C to 40°C, -80°C to 10°C, -70°C to 0°C, -70°C to -10°C, -70°C to -20°C, -70°C to -30°C, -70°C to -40°C, -70°C to -50°C, or -80°C to -40°C. In some embodiments, the polymeric material has at least two glass transition temperatures. In some embodiments, the polymeric material has a first Tg of less than 40°C. g and a second T greater than 60°C g 、The first T is less than 0℃ g and a second T greater than 60°C g 、The first T is less than 0℃ g and a second T greater than 75°C g , or the first T less than -20℃ g and a second T greater than 80°C g .

[0224] In some embodiments, the polymeric material is transparent, substantially transparent, mostly transparent, or opaque. In certain embodiments, the polymeric material is transparent. In certain embodiments, the polymeric material is substantially transparent. In certain embodiments, the polymeric material is mostly transparent. In some embodiments, greater than 70% of visible light passes through the polymeric material. In certain embodiments, greater than 80% of visible light passes through the polymeric material. In certain embodiments, greater than 90% of visible light passes through the polymeric material. In certain embodiments, greater than 95% of visible light passes through the polymeric material. In certain embodiments, greater than 99% of visible light passes through the polymeric material. Transparency can be measured using a UV-Vis spectrophotometer. In some embodiments, transparency is measured by measuring the passage of a transparency wavelength. In some embodiments, greater than 70%, greater than 80%, greater than 90%, greater than 95%, or greater than 99% of a transparency wavelength can pass through the polymeric material. In some embodiments, the transparency wavelength is within the visible light range (i.e., from 400 nm to 800 nm), within the infrared range, or within the ultraviolet range. In some embodiments, the polymeric material has no color. In other embodiments, the polymeric material appears white, off-white, or mostly transparent white as detected by the human eye.

[0225] In some embodiments, greater than 20%, greater than 30%, greater than 40%, greater than 50%, greater than 60%, greater than 70%, greater than 80%, greater than 90%, or greater than 95% of visible light passes through the polymeric material after 24 hours in a humid environment at 37° C. In a preferred embodiment, greater than 70% of visible light passes through the polymeric material after 24 hours in a humid environment at 37° C.

[0226] In some embodiments, the polymeric material is biocompatible, bioinert, or a combination thereof.

[0227] In some embodiments, the polymeric material is formed using photopolymerization using 3D printing (i.e., by additive manufacturing). In certain embodiments, the polymeric material is formed using a conventional 3D printer. In some embodiments, the polymeric material can be used in coatings, molds, injection molding machines, or other manufacturing methods that use or may use light during the curing process. In some embodiments, the polymeric material is well suited for applications requiring, for example, solvent resistance, moisture resistance, water resistance, creep resistance, or heat deformation resistance.

[0228] D. Printable resin

[0229] The polymeric materials disclosed herein can be formed from printable resins. In some embodiments, weak crosslinks, strong crosslinks, polymer chains, and ring monomers can be used alone or in combination with any of the disclosed herein to form printable resins.

[0230] i. Weak covalent crosslinking

[0231] The polymer material disclosed herein can be formed from a printable resin. In some embodiments, the present disclosure provides a printable resin for forming a polymer material comprising weak cross-linked covalent bonds and / or weak cross-linked units comprising weak covalent bonds. In some embodiments, the printable resin includes a weak cross-linked unit, which includes multiple weak covalent bonds. In some embodiments, the present disclosure provides a printable resin comprising: a plurality of monomers; a weak cross-linked unit comprising a first end and a second end, the weak cross-linked unit comprising a weak cross-linked bond located between the first end and the second end; and an initiator. In some embodiments, the weak cross-linked bond has a weak bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some embodiments, a plurality of monomers are contained in an oligomer. In some embodiments, a plurality of monomers comprise an oligomer. In certain embodiments, the oligomer has an average chain length of 1 kDa to 20 kDa.

[0232] In some embodiments, the present disclosure provides a printable resin comprising: a plurality of monomers; an activatable unit; and an initiator. In some embodiments, the activatable unit is converted into a weak crosslinking unit when activated by a catalyst, and the weak crosslinking unit includes a weak crosslinking bond located between a first end of the weak crosslinking unit and a second end of the weak crosslinking unit. In some embodiments, the weak crosslinking bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some embodiments, the plurality of monomers are contained in an oligomer. In some embodiments, the plurality of monomers comprise an oligomer. In certain embodiments, the oligomer has an average chain length of 1 kDa to 20 kDa. In some embodiments, the printable resin further comprises a catalyst. In some embodiments, the resin forms the activatable unit in situ.

[0233] In some embodiments, the present disclosure provides a printable resin comprising: a plurality of monomers, the plurality of monomers comprising a first monomer comprising a first weak bond-forming unit and a second monomer comprising a second weak bond-forming unit; and an initiator. In some embodiments, the first weak bond-forming unit and the second weak bond-forming unit combine to form a weak crosslinking unit, the weak crosslinking unit comprising a first end and a second end, and a weak crosslinking bond between the first monomer and the second monomer. Figure 10AThe example of a plurality of monomers including a first monomer and a second monomer is shown, wherein the first monomer includes a first weak bond forming unit, and the second monomer includes a second weak bond forming unit, wherein the first and second monomers are combined to form a weak bond between the first monomer and the second monomer. In some embodiments, the weak cross-linking bond has a weak bond dissociation energy of 50kJ / mol to 325kJ / mol. In certain embodiments, at least some of the plurality of monomers are included in an oligomer. In some embodiments, the plurality of monomers include oligomers. In certain embodiments, the oligomer has an average chain length of 1kDa to 20kDa.

[0234] In some embodiments, the weak cross-linking unit is a weak cross-link (ie, a covalent bond). In some embodiments, the chain length of the weak cross-linking unit is 30 Da to 5,000 Da.

[0235] In some embodiments, the first end of the weak crosslinking unit includes a first terminal reactive functional group. In a preferred embodiment, the first terminal reactive functional group is selected from acrylate, methacrylate, vinyl ester, maleate, fumarate, thiol, epoxide, allyl ether, alkene, alkyne, hydroxyl, amine, isocyanate, aldehyde (and / or ketone), derivatives thereof, and combinations thereof.

[0236] In some embodiments, the second end of the weak crosslinking unit includes a second terminal reactive functional group. In a preferred embodiment, the second terminal reactive functional group is selected from acrylate, methacrylate, vinyl ester, maleate, fumarate, thiol, epoxide, allyl ether, alkene, alkyne, hydroxyl, amine, isocyanate, aldehyde (and / or ketone), derivatives thereof, and combinations thereof.

[0237] In some embodiments, the weak cross-linking bond is a peroxide (OO bond), a disulfide (SS bond), a CP bond, a CO bond, a CS bond, a NN bond, a NP bond, a NO bond, a NC bond, an OS bond, a Si-Si bond, a Si-S bond, a P-Si, a PP bond, a Se-C bond, a Se-S bond, a Se-Se bond, a Bi-C bond, a benzyl group attached to a carbon or heteroatom, or a C(O)-C(O) bond. Figure 7A An exemplary synthesis of nitrogen-based cross-linking units is shown. Figure 7B Exemplary nitrogen-based cross-linking units are shown, with weak covalent bonds indicated by arrows. Figure 7C Exemplary sulfur-based cross-linking units are shown, with weak covalent bonds indicated by arrows. Figure 7D Exemplary diketone-based cross-linking units are shown.

[0238] In some embodiments, the weak crosslinking unit has the chemical structure of Formula Ia, or a derivative thereof:

[0239]

[0240] In some embodiments, the weak crosslinking unit has a chemical structure of Formula II-a, or a derivative thereof:

[0241]

[0242] In some embodiments, the weak crosslinking unit has a chemical structure of Formula III-a, or a derivative thereof:

[0243]

[0244] In some embodiments, the bond dissociation energy of the weak crosslinks is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, between 50 kJ / mol and 300 kJ / mol, between 55 kJ / mol and 250 kJ / mol, or between 60 kJ / mol and 200 kJ / mol. In some embodiments, the weak crosslinks have a strength less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond strength in polyethylene.

[0245] In some embodiments, the oligomer comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak cross-links.

[0246] In some embodiments, the printable resin comprises a ratio of the longest length of the weakly crosslinked unit to the longest length of the oligomer, wherein the ratio is less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500. In some embodiments, the printable resin comprises a ratio of the longest length of the weakly crosslinked unit to the longest length of the oligomer, wherein the ratio is 1:5 to 1:200, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:75 to 1:200, 1:10 ... :5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:75 to 1:100, 1:100 to 1:500, 1:200 to 1:500, 1:300 to 1:500, 1:400 to 1:500, or less than or equal to 1:500.

[0247] In some embodiments, the printable resin further comprises a strong crosslinking unit, wherein the strong crosslinking unit comprises a first end and a second end, and the strong crosslinking unit comprises one or more bonds forming a chain connected to the first end and the second end. Printable resins comprising strong crosslinking units are generally photocurable products with statistically higher molecular weights, thereby increasing toughness. In some embodiments, the addition of strong crosslinking units increases the early average kinetic chain length during polymerization, but the product does not form a thermoset or gel. In some embodiments, each of the one or more bonds in the strong crosslinking unit has a bond dissociation energy greater than or equal to 280 kJ / mol or greater than or equal to 300 kJ / mol. In some embodiments, the bond dissociation energy of each of the one or more bonds in the strong crosslinking unit is at least 20 kJ / mol, at least 40 kJ / mol, at least 80 kJ / mol, at least 120 kJ / mol, at least 150 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak crosslinking bond.

[0248] In some embodiments, the printable resin further comprises a third monomer comprising a first strong bond forming unit; and a fourth monomer comprising a second strong bond forming unit, wherein the first strong bond forming unit and the second strong bond forming unit combine to form a strong cross-linking unit located between the third monomer and the fourth monomer. Figure 10BAn example of a printable resin is shown, comprising a first monomer comprising a first weak bond-forming unit, a second monomer comprising a strong weak bond-forming unit, a third monomer comprising a first strong bond-forming unit, and a fourth monomer comprising a second strong bond-forming unit, wherein the first weak bond-forming unit and the second weak bond-forming unit combine to form a weak cross-link, and the first strong bond-forming unit and the second strong bond-forming unit combine to form a strong cross-link. In some embodiments, the strong cross-link comprises one or more bonds. In some embodiments, the one or more bonds each have a bond dissociation energy greater than or equal to 280 kJ / mol or greater than or equal to 300 kJ / mol. In some embodiments, the bond dissociation energy of each of the one or more bonds is at least 20 kJ / mol, at least 40 kJ / mol, at least 80 kJ / mol, at least 100 kJ / mol, at least 120 kJ / mol, at least 150 kJ / mol, or at least 200 kJ / mol greater than the bond dissociation energy of the weak cross-link. In some embodiments, the strong cross-link is formed in situ by the resin comprising the components.

[0249] In some embodiments, the first end of the strong crosslinking unit includes a first terminal reactive functional group, the second end of the strong crosslinking unit includes a second terminal reactive group, or a combination thereof.

[0250] In some embodiments, the printable resin comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 1 wt%, less than 0.5 wt%, or less than 0.1 wt% of weakly crosslinked units.

[0251] In some embodiments, the weak cross-linking bond is selected from peroxide (OO bond), disulfide (SS bond), CP bond, CO bond, CS bond, NN bond, NP bond, NO bond, NC bond, OS bond, Si-Si bond, Si-S bond, P-Si, PP bond, Se-C bond, Se-S bond, Se-Se bond, Bi-C bond, benzyl group connected to carbon or heteroatom, or C(O)-C(O) bond and combination thereof. In some embodiments, the weak cross-linking bond is a non-polar covalent bond or a polar covalent bond. It is understood by those skilled in the art that the molecular structure around the bond can contribute to the bond dissociation energy. As a non-limiting example, the bond dissociation energy of a disulfide bond can be greater than 300 kJ / mol in some molecular arrangements, but less than 300 kJ / mol in other molecular arrangements. In some embodiments, molecular modeling is used to predict molecular structures that result in low bond dissociation energies.

[0252] In some embodiments, the weak crosslinks comprise Diels-Alder bonds. Exemplary Diels-Alder adducts and their synthesis are shown in Figure 8AAs shown. Under stress, the Diels-Alder adduct can dissociate. In some embodiments, the bond to the coordination or ligand is also a weak cross-linking bond. Figure 8A As shown, the adduct may contain a reactive group ("RG"), for example, an epoxide, an acrylate, or a thiol. Figure 8B The polymerization of the reactive groups of the Diels-Alder adduct into a polymer network is shown (dashed lines). Figure 8C It is shown that when the polymer network is strained, tension applied to the Diels-Alder adduct results in stress being placed on the crosslinks. Figure 8D The dissociation of the Diels-Alder adduct is shown, relieving some of the stress in the polymer network. New adducts can be formed, possibly with new configurations. If the double bond in the Diels-Alder adduct reacts (e.g. Figure 8B ), which locks the adduct so that it cannot dissociate as easily as the unreacted part. Figure 8E The synthesis of exemplary Diels-Alder adducts described herein is shown. Diels-Alder crosslinking units can be polymerized into the material to form weak crosslinking units. Optionally, an excess of furfuryl methacrylate can be present in the formulation to allow for easy reformation of the Diels-Alder bonds after the initial dissociation of the Diels-Alder adduct. Figure 8F Another synthesis of an exemplary Diels-Alder adduct is shown. The Diels-Alder crosslinking unit can optionally be esterified at the carboxylic acid. Depending on the reaction conditions and the reactants used, some Diels-Alder adducts can copolymerize through the olefin in the adduct, in which case the crosslinking unit becomes a strong crosslink because dissociation of the adduct is no longer possible.

[0253] In some embodiments, the resin comprises oligomers and / or polymers containing weak covalent crosslinks in the side groups of the oligomers and / or polymers. In some embodiments, the side groups comprise reactive functional groups to facilitate incorporation into the final cured crosslinked network. Figure 9A The polymerization of methacrylate with other monomers into a polymer matrix is shown, in which weak crosslinking moieties (including hydroxyl reactive groups) are freely diffused and unreacted. Figure 9B It is shown that after the post-curing heating step, the hydroxyl groups react with the isocyanate to form weak crosslinking units throughout the network. In some embodiments, the weak covalent bond is located in the crosslinking unit between two oligomers and / or polymers having reactive end groups. In some embodiments, the weak covalent crosslink is contained in a star-shaped, hyperbranched, or dendritic oligomer or polymer, or a combination thereof, containing reactive functional groups as end groups.

[0254] In some embodiments, the printable resin includes a plurality of oligomers having an average oligomer chain length; and a plurality of weak crosslinking units having an average weak crosslinking unit chain length, wherein the weak crosslinking unit average chain length is less than the oligomer average chain length. In some embodiments, the resin has a ratio of the weak crosslinking unit average chain length to the oligomer average chain length, and wherein the ratio is 1:1.1 to 1:100, 1:2 to 1:100, 1:5 to 1:100, 1:10 to 1:100, 1:20 to 1:100, 1:30 to 1:100, 1:40 to 1:100, 1:50 to 1:100, 1:10 to 1:200, 1:20 to 1:200, 1:30 to 1:200, 1:40 to 1:200, 1:50 to 1:200, 1:100 to 1:100 200, less than or equal to 1:2, less than or equal to 1:3, less than or equal to 1:4, less than or equal to 1:5, less than or equal to 1:6, less than or equal to 1:7, less than or equal to 1:8, less than or equal to 1:9, less than or equal to 1:10, less than or equal to 1:20, less than or equal to 1:30, less than or equal to 1:40, less than or equal to 1:50, less than or equal to 1:75, less than or equal to 1:100, less than or equal to 1:200, less than or equal to 1:300, less than or equal to 1:400, or less than or equal to 1:500.

[0255] In some embodiments, the weak crosslinking unit comprises a polymerizable group. In some embodiments, the polymerizable group is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, aldehyde, ketone, derivatives thereof, and combinations thereof.

[0256] In some embodiments, the oligomer includes a polymerizable group. In some embodiments, the polymerizable group of the oligomer is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, aldehyde, ketone, derivatives thereof, and combinations thereof.

[0257] ii. Loops within the chain

[0258] The polymeric materials disclosed herein can be formed from printable resins. In some embodiments, the present disclosure provides printable resins for forming polymer chains and / or polymeric materials comprising ring monomers. In some embodiments, the printable resin includes a ring monomer comprising a ring containing three or more ring members, a first bond located between two ring members of a first group and having a bond dissociation energy of less than 325 kJ / mol, and a second bond located between two ring members of a second group and having a bond dissociation energy greater than the bond dissociation energy of a weak bond. In some embodiments, the second bond has a bond dissociation energy greater than 325 kJ / mol. In some embodiments, the ring monomer further comprises a first linker attached to the ring comprising a first reactive group and a second linker attached to the ring comprising a second reactive group. Figures 7A-7D Non-limiting examples of such cyclic monomers are shown. In some embodiments, the printable resin includes a plurality of monomers. In some embodiments, the printable resin includes a plurality of cyclic monomers. In some embodiments, the plurality of monomers are contained in oligomers having an average chain length of 1 kDa to 30 kDa.

[0259] In some embodiments, a printable resin comprises: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 30 kDa; and a ring monomer comprising: three or more ring members; a first bond located between a first set of two ring members and having a bond dissociation energy of less than 325 kJ / mol; a second bond located between a second set of two ring members and having a bond dissociation energy greater than the first bond; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group. In some embodiments, the second bond has a bond dissociation energy greater than 325 kJ / mol.

[0260] In some embodiments, the printable resin includes: a plurality of monomers, optionally wherein the plurality of monomers are contained in an oligomer having an average chain length of 1 kDa to 30 kDa; and a ring monomer comprising: three or more ring members; a first bond located between a first set of two ring members, wherein upon activation of a catalyst, the first bond is convertible into a bond having a bond dissociation energy of less than 325 kJ / mol (i.e., the first bond is an activatable unit); a second bond located between a second set of two ring members and having a bond dissociation energy greater than the first bond; a first linker attached to the ring comprising a first reactive group; and a second linker attached to the ring comprising a second reactive group. In some embodiments, the second bond has a bond dissociation energy greater than 325 kJ / mol. In some embodiments, the resin further comprises a catalyst.

[0261] In some embodiments, the first linker is covalently attached to the ring. In some embodiments, the second linker is covalently attached to the ring. In some embodiments, the first linker, the second linker, or a combination thereof are each located outside the ring (e.g., excluding bonds within three or more members of the ring).

[0262] In some embodiments, the first linker comprises a first reactive functional group. In some embodiments, the first reactive functional group is selected from acrylates, methacrylates, vinyl esters, maleates, fumarates, thiols, epoxides, allyl ethers, alkenes, alkynes, hydroxyls, amines, isocyanates, aldehydes (and / or ketones), derivatives thereof, and combinations thereof.

[0263] In some embodiments, the second end connector includes a second reactive functional group. In some embodiments, the second reactive functional group is selected from acrylates, methacrylates, vinyl esters, maleates, fumarates, thiols, epoxides, allyl ethers, alkenes, alkynes, hydroxyls, amines, isocyanates, aldehydes (and / or ketones), derivatives thereof, and combinations thereof.

[0264] In some embodiments, the weak bond is a peroxide (OO bond), a disulfide (SS bond), a CP bond, a CO bond, a CS bond, a NN bond, a NP bond, a NO bond, a NC bond, an OS bond, a Si-Si bond, a Si-S bond, a P-Si, a PP bond, a Se-C bond, a Se-S bond, a Se-Se bond, a Bi-C bond, a benzyl group attached to a carbon or heteroatom, or a C(O)-C(O) bond.

[0265] In some embodiments, the ring monomer has the chemical structure of Formula Ib, or a derivative thereof:

[0266]

[0267] In some embodiments, the ring monomer has the chemical structure of Formula II-b, or a derivative thereof:

[0268]

[0269] In some embodiments, the ring monomer has the chemical structure of Formula III-b, or a derivative thereof:

[0270]

[0271] In some embodiments, the ring monomer has the chemical structure of Formula IV-b, or a derivative thereof:

[0272]

[0273] In some embodiments, the ring monomer has the chemical structure of Formula Vb, or a derivative thereof:

[0274]

[0275] In some embodiments, the ring monomer has the chemical structure of Formula VI-b, or a derivative thereof:

[0276]

[0277] In some embodiments, cyclic monomer includes at least one reactive functional group. In some embodiments, cyclic monomer includes at least two reactive functional groups (for example, at the first joint and the second joint). Non-limiting examples of reactive functional groups include free radical polymerizable functional groups, photoactive groups, groups promoting stepwise growth polymerization, thermoreactive groups and / or groups promoting key formation (for example, covalent bond formation). In some embodiments, reactive functional groups are polymerizable groups. In some embodiments, reactive functional groups can be initiated with photocatalysts and / or photoinitiators. In some embodiments, reactive functional groups include polymerizable unsaturated bonds and / or ring-opening groups. In some embodiments, the reactive functional groups include acrylates, methacrylates, acrylamides, vinyl groups, vinyl ethers, thiols, alcohols, allyl ethers, norbornenes, vinyl acetates, maleates, fumarates, maleimides, epoxides, vinyl esters, styrenes, butadienes, alkenes, ring-strained cyclic ethers, ring-strained thioethers, cyclic esters, cyclic carbonates, cyclic silanes, cyclic siloxanes, hydroxyls, amines, isocyanates, aldehydes, ketones, blocked isocyanates, acid chlorides, activated esters, Diels-Alder reactive groups, furans, cyclopentadienes, anhydrides, groups that favor photodimerization (e.g., anthracene, acenaphthylene, and / or coumarin), groups that photodegrade into reactive species (e.g., Norrish Type 1 and Type 2 materials), azides, nitrene-generating groups, carbene-generating groups, derivatives thereof, or combinations thereof. In some embodiments, the reactivity of the reactive functional groups is thermally and / or photochemically controllable.

[0278] In some embodiments, the first reactive functional group and the second reactive group are the same. In some embodiments, the first reactive functional group and the second reactive group are different functional groups.

[0279] In some embodiments, the bond dissociation energy of the first bond (i.e., weak bond) is less than or equal to 300 kJ / mol, less than or equal to 275 kJ / mol, less than or equal to 250 kJ / mol, less than or equal to 225 kJ / mol, less than or equal to 200 kJ / mol, less than or equal to 175 kJ / mol, less than or equal to 150 kJ / mol, 50 kJ / mol to 300 kJ / mol, 55 kJ / mol to 250 kJ / mol, or 60 kJ / mol to 200 kJ / mol. In some embodiments, the first bond (i.e., weak bond) has less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%, less than 35%, less than 30%, less than 25%, or less than 20% of the average carbon-carbon bond strength in polyethylene.

[0280] In some embodiments, the oligomer comprises a backbone wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol, at least 30 kJ / mol, at least 40 kJ / mol, at least 50 kJ / mol, at least 60 kJ / mol, at least 70 kJ / mol, at least 80 kJ / mol, at least 90 kJ / mol, at least 100 kJ / mol, at least 125 kJ / mol, at least 150 kJ / mol, at least 175 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weaker bonds.

[0281] In some embodiments, the printable resin further comprises a crosslinking unit, wherein the crosslinking unit comprises a first end and a second end, and the crosslinking unit comprises one or more bonds forming a chain connected to the first end and the second end. Printable resins comprising crosslinking units are generally photocurable products with statistically higher molecular weights, thereby increasing toughness. In some embodiments, the addition of crosslinking units increases the early average kinetic chain length during polymerization, but the product does not form a thermoset or gel. In some embodiments, each of the one or more bonds in the crosslinking unit has a bond dissociation energy greater than or equal to 280 kJ / mol or greater than or equal to 300 kJ / mol. In some embodiments, the bond dissociation energy of each of the one or more bonds in the crosslinking unit is at least 20 kJ / mol, at least 40 kJ / mol, at least 80 kJ / mol, at least 120 kJ / mol, at least 150 kJ / mol, or at least 200 kJ / mol higher than the bond dissociation energy of the weak bond.

[0282] In some embodiments, the printable resin comprises 0.1 wt% to 50 wt%, 1 wt% to 30 wt%, 2 wt% to 10 wt%, less than 10 wt%, less than 5 wt%, less than 1 wt%, less than 0.5 wt%, or less than 0.1 wt% of the cyclic monomer.

[0283] In some embodiments, the weak bond is selected from a peroxide (OO bond), a disulfide (SS bond), a CP bond, a CO bond, a CS bond, a NN bond, a NP bond, a NO bond, a NC bond, an OS bond, a Si-Si bond, a Si-S bond, a P-Si, a PP bond, a Se-C bond, a Se-S bond, a Se-Se bond, a Bi-C bond, a benzyl group attached to a carbon or heteroatom, or a C(O)-C(O) bond and combinations thereof. In some embodiments, the weak bond is a non-polar covalent bond or a polar covalent bond. It is understood by those skilled in the art that the molecular structure surrounding the bond can contribute to the bond dissociation energy. As a non-limiting example, the bond dissociation energy of a disulfide bond can be greater than 300 kJ / mol in certain molecular arrangements, but less than 300 kJ / mol in other molecular arrangements. In some embodiments, molecular modeling is used to predict molecular structures that result in low bond dissociation energies.

[0284] In some embodiments, the ring and / or weak bridge comprises a Diels-Alder unit. Under stress, the Diels-Alder adduct can dissociate. In some embodiments, the bond to the coordination or ligand is also a weak bond. Depending on the reaction conditions and the reactants used, some Diels-Alder adducts can copolymerize with the olefin in the adduct. In this case, the weak bond (e.g., the Diels-Alder adduct) becomes a strong bond because dissociation of the adduct is no longer possible. In some embodiments, polymers containing cyclic units contain Diels-Alder adducts that act as weak bridges. In some embodiments, a certain percentage of the Diels-Alder adducts react (i.e., become inactivated toward the reverse Diels-Alder reaction) and thus no longer serve as weak bridges in the ring. In some embodiments, less than 5%, less than 10%, less than 20%, less than 30%, less than 40%, less than 50%, less than 60%, less than 70%, less than 80%, or less than 90% of the Diels-Alder adducts are inactivated. In some embodiments, less than 30% of the Diels-Alder adducts are inactivated. In some embodiments, less than 10% of the Diels-Alder adduct is inactivated.

[0285] In some embodiments, the ring monomer includes a polymerizable group. In some embodiments, the polymerizable group is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, aldehyde, ketone, isocyanate, acyl halide, anhydride, low molecular weight ester (i.e., less than 200g / mol), carboxylic acid, silanol, silane, chlorosilane, cyclic siloxane, alkoxysilane, its derivatives and combinations thereof. In some embodiments, the ring monomer includes at least two polymerizable groups.

[0286] In some embodiments, the oligomer includes a polymerizable group. In some embodiments, the polymerizable group of the oligomer is selected from vinyl, allyl, allyl ether, acrylate, methacrylate, acrylamide, epoxy, oxetane, thiol, hydroxyl, amine, aldehyde, ketone, isocyanate, acyl halide, anhydride, low molecular weight ester (i.e., less than 200 g / mol), carboxylic acid, silanol, silane, chlorosilane, cyclic siloxane, alkoxysilane, derivatives thereof, and combinations thereof.

[0287] In some embodiments, a plurality of loops are incorporated into the material. In certain embodiments, the plurality of loops includes loops of more than one size (e.g., more than one ring size). As a non-limiting example, a material including a plurality of loops may include 10% loops having 10 ring members, 80% loops having 8 ring members, and 10% loops having 20 ring members.

[0288] In some embodiments, at least some of the cyclic units contain more than one loop in the cyclic monomer. In certain embodiments, each of the more than one loops includes a weak bond. As a non-limiting example, Figure 15A A loop monomer is shown, wherein the ring comprises multiple rings, including a ring having a short chain comprising a first weak bond and a medium-length chain having a second weak bond. In some embodiments, the loop monomer comprises a single ring comprising multiple weak bonds. As a non-limiting example, Figure 15B A loop monomer is shown, wherein the loop comprises a first weak bond positioned along the short chain and a second weak bond positioned along the long chain. In some embodiments, the loop monomer comprises multiple loops that share a weak bond. As a non-limiting example, Figure 15C A loop monomer is shown that includes two rings (e.g., a first ring that includes a top semicircular polymer chain, and a second ring that includes a bottom semicircular polymer chain) that share a weak bond. In some embodiments, the first weak bond has a higher bond dissociation energy than the second weak bond. In some embodiments, the second weak bond has a higher bond dissociation energy than the first weak bond. In some embodiments, the second weak bond and the first weak bond have the same bond dissociation energy. In some embodiments, Figure 15A The reactive group represented in -C represents the connection to the polymer network.

[0289] iii. Other printable resin properties

[0290] In some embodiments, the printable resin includes oligomers with an average chain length of 1 kDa to 20 kDa, and the oligomers include at least some of the multiple monomers. In some embodiments, the resin includes multiple unreacted monomers and at least one oligomer with a chain length of 1 kDa to 20 kDa. In some embodiments, the oligomer has an average chain length greater than 20 kDa. In some embodiments, the multiple monomers include oligomers or polymers. In certain embodiments, the multiple monomers consist essentially only of oligomers or polymers. In some embodiments, the multiple monomers consist only of oligomers or polymers.

[0291] In some embodiments, the printable resin includes oligomers with an average chain length of 1 kDa to 30 kDa, and the oligomers include at least some of the multiple monomers. In some embodiments, the resin includes a plurality of unreacted monomers and at least one oligomer with a chain length of 1 kDa to 30 kDa. In some embodiments, the oligomer has an average chain length greater than 30 kDa. In some embodiments, the multiple monomers include oligomers or polymers. In certain embodiments, the multiple monomers consist essentially only of oligomers or polymers. In some embodiments, the multiple monomers consist only of oligomers or polymers. In some embodiments, the multiple monomers consist only of monomers comprising a ring disclosed herein.

[0292] In some embodiments, the printable resin includes an initiator that is a photoinitiator. Photoinitiators can be used for various purposes, including for curing polymers, including those that can be activated by light and initiate polymerization of the polymerizable components of the formulation. In embodiments, the photoinitiator is a free radical photoinitiator and / or a cationic initiator. In some embodiments, the photoinitiator is a Type I photoinitiator, which undergoes unimolecular bond cleavage to produce free radicals. In another embodiment, the photoinitiator is a Type II photoinitiator, which undergoes a bimolecular reaction to produce free radicals. Common Type I photoinitiators include, but are not limited to, benzoin ethers, benzil ketals, α-dialkoxyacetophenones, α-hydroxyalkyl acylphenones, and acylphosphine oxides. Common Type II photoinitiators include benzophenone / amine and thioxanthone / amine. Cationic initiators include aryldiazonium, diaryliodonium, and triarylsulfonium salts. In a preferred embodiment, the photoinitiator comprises diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide, ethyl (2,4,6-trimethylbenzoyl) phenyl phosphinate or a combination thereof. In certain preferred embodiments, the photoinitiator comprises a free radical photoinitiator, a cationic initiator and / or a photobase generator. In some preferred embodiments, the photoinitiator is a Type I photoinitiator that undergoes unimolecular bond cleavage to generate free radicals, or a Type II photoinitiator that undergoes a bimolecular reaction to generate free radicals. In some preferred embodiments, the Type I photoinitiator is a benzoin ether, a benzil ketal, an α-dialkoxyacetophenone, an α-hydroxyalkyl acylphenone or an acylphosphine oxide. In some preferred embodiments, the Type II photoinitiator is a benzophenone / amine, camphorquinone / amine, or thioxanthone / amine. In some embodiments using a Type II photoinitiator, a donor other than an amine (e.g., a borate) is used. In some preferred embodiments, the cationic initiator is an aryldiazonium, a diaryliodonium or a triarylsulfonium salt. In certain embodiments, the photoinitiator undergoes Type I, Type II, electron transfer, and / or hydrogen abstraction.

[0293] In some embodiments, the photoinitiator uses light energy to initiate photopolymerization. In certain embodiments, the photoinitiator initiates photopolymerization by exposure to light energy of 800nm to 250nm, 800nm to 350nm, 800nm to 450nm, 800nm to 550nm, 800nm to 650nm, 600nm to 250nm, 600nm to 350nm, 600nm to 450nm, or 400nm to 250nm. In some embodiments, the photoinitiator initiates photopolymerization after absorbing two photons, which can use longer wavelength light to initiate photopolymerization. In some embodiments, more than one photoinitiator is used, and each photoinitiator is activated at a different wavelength and or at a different time. As a non-limiting example, one photoinitiator can be activated during the printing stage and a second photoinitiator can be activated during the post-curing stage. In some embodiments where more than one initiator is used, they are activated at different wavelengths, or they are activated using different energy sources (e.g., heat, ultrasound, infrared, radiofrequency heating); activation of each initiator can occur simultaneously (e.g., both heat activation and infrared activation are performed simultaneously) or at different times.

[0294] In some embodiments, the resin comprises more than one initiator (e.g., 2, 3, 4, 5, or more than 5 initiators). In some embodiments, the initiator is a thermal initiator. In certain embodiments, the thermal initiator comprises an organic peroxide. In some embodiments, the thermal initiator comprises an azo compound, an inorganic peroxide, an organic peroxide, or any combination thereof. In some embodiments, the thermal initiator is selected from tert-amyl peroxybenzoate, 4,4-azobis(4-cyanovaleric acid), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobisisobutyronitrile (AIBN), benzoyl peroxide, 2,2-bis(tert-butylperoxy)butane, 1,1-bis(tert-butylperoxy)cyclohexane, 2,5-bis(tert-butylperoxy-2,5-dimethylhexane, 2,5-bis(tert-butylperoxy)-2,5-dimethyl-3-hexyne, bis(1-(tert-butylperoxy) -3,3,5-trimethylcyclohexane, tert-butyl hydroxyperoxide, tert-butyl peracetate, tert-butyl peroxide, tert-butyl peroxybenzoate, tert-butylperoxyisopropyl carbonate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2,4-pentanedione peroxide, peracetic acid, potassium persulfate, derivatives thereof, and combinations thereof. In a preferred embodiment, the thermal initiator comprises azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), benzoyl peroxide, or combinations thereof.

[0295] In some embodiments, the printable resin comprises 0.01-10 wt%, 0.02-5 wt%, 0.05-4 wt%, 0.1-3 wt%, 0.1-2 wt%, or 0.1-1 wt% of an initiator. In a preferred embodiment, the printable resin comprises 0.1-2 wt% of an initiator. In some embodiments, the printable resin comprises 0.01-10 wt%, 0.02-5 wt%, 0.05-4 wt%, 0.1-3 wt%, 0.1-2 wt%, or 0.1-1 wt% of a photoinitiator. In a preferred embodiment, the printable resin comprises 0.1-2 wt% of a photoinitiator. In some embodiments, the printable resin comprises 0 to 10 wt%, 0 to 9 wt%, 0 to 8 wt%, 0 to 7 wt%, 0 to 6 wt%, 0 to 5 wt%, 0 to 4 wt%, 0 to 3 wt%, 0 to 2 wt%, 0 to 1 wt%, or 0 to 0.5 wt% of a thermal initiator. In a preferred embodiment, the printable resin comprises 0 to 0.5 wt% of a thermal initiator.

[0296] Non-limiting examples of reactive functional groups include free radical polymerizable functional groups, photoactive groups, groups that promote step-growth polymerization, thermally reactive groups, and / or groups that promote bond formation (e.g., covalent bond formation). In some embodiments, the functional group includes acrylate, methacrylate, acrylamide, vinyl, vinyl ether, thiol, allyl ether, norbornene, vinyl acetate, maleate, fumarate, maleimide, epoxide, ring-strained cyclic ether, ring-strained thioether, cyclic ester, cyclic carbonate, cyclic silane, cyclic siloxane, hydroxyl, amine, isocyanate, aldehyde, ketone, blocked isocyanate, acid chloride, activated ester, Diels-Alder reactive group, furan, cyclopentadiene, anhydride, a group that favors photodimerization (e.g., anthracene, acenaphthylene, or coumarin), a group that photodegrades into reactive species (e.g., Norrish Type 1 and Type 2 materials), azide, derivatives thereof, or combinations thereof.

[0297] In some embodiments, the first terminal reactive functional group and the second terminal reactive group are the same. In other embodiments, the first terminal reactive functional group and the second terminal reactive group are different functional groups.

[0298] In some embodiments, the printable resins disclosed herein contain less than 10 wt%, less than 9 wt%, less than 8 wt%, less than 7 wt%, less than 6 wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, or less than 1 wt% hydrogen bonding units. In a preferred embodiment, the printable resin contains less than 5 wt% hydrogen bonding units. In a more preferred embodiment, the printable resin contains less than 2 wt% hydrogen bonding units.

[0299] In some embodiments, the oligomer comprises a plurality of monomers, each of which is covalently bonded to a backbone having a bond dissociation energy greater than or equal to 280 kJ / mol or greater than or equal to 300 kJ / mol. In some embodiments, the oligomer comprises a plurality of monomers, each of which is covalently bonded to a backbone having a bond dissociation energy greater than or equal to 280 kJ / mol or greater than or equal to 300 kJ / mol. In some embodiments, the oligomer comprises a plurality of monomers, each of which is covalently bonded to a backbone having a bond dissociation energy greater than or equal to 20 kJ / mol, at least 40 kJ / mol, at least 80 kJ / mol, at least 100 kJ / mol, at least 120 kJ / mol, at least 150 kJ / mol, or at least 200 kJ / mol greater than a weak covalent bond.

[0300] In some embodiments, the printable resin further comprises a reactive diluent, a crosslinking modifier, a light blocker, a solvent, a glass transition temperature modifier, a thermal initiator, a catalyst for activating the activatable units, or a combination thereof. In some embodiments, the resin further comprises at least one of a polymerization catalyst, an inhibitor, a plasticizer, a surface energy modifier, a pigment, a dye, a filler, a binder, a seed crystal, a crystallization catalyst, a bioagent, a catalyst for selective bond breaking, or any combination thereof.

[0301] In some embodiments, the viscosity of the printable resin at the printable temperature is less than 60 PaS, less than 50 PaS, less than 40 PaS, less than 30 PaS, less than 20 PaS, less than 10 PaS, less than 9 PaS, less than 8 PaS, less than 7 PaS, less than 6 PaS, less than 5 PaS, less than 4 PaS, less than 3 PaS, less than 2 PaS, less than 1 PaS, or less than 1 PaS. In some embodiments, the printable temperature is at, above, or below room temperature. In some embodiments, the printable temperature is between 0°C and 25°C, between 25°C and 40°C, between 40°C and 100°C, or between 25°C and 150°C. In preferred embodiments, the viscosity of the resin at the printable temperature is between 0.5 PaS and 20 PaS. In preferred embodiments, the printable temperature is between 70°C and 110°C. In some embodiments, the printable temperature is 90°C. In certain preferred embodiments, the viscosity of the printable resin at 90°C is between 0.5 PaS and 20 PaS. In certain preferred embodiments, the printable resin has a viscosity of 20 PaS to 60 PaS at 90°C.

[0302] The dynamic viscosity of a fluid indicates its resistance to shear flow. The SI unit for dynamic viscosity is poise (Pa·s). Dynamic viscosity is usually given in centipoise, where 1 centipoise (cP) is equal to 1 mPa·s. Kinematic viscosity is the ratio of dynamic viscosity to the density of the fluid; the SI unit is m 2 / s. Devices for measuring viscosity include viscometers and rheometers. The viscosity of the compositions described herein can be measured at 110°C using a rheometer. For example, Anton Paar's MCR 301 rheometer can be used for rheological measurements in rotational mode (PP-25, 50 s-1, 50-115°C, 3°C / min).

[0303] In some embodiments, the printable resin is capable of being 3D printed (ie, can be used for additive manufacturing).

[0304] In some embodiments, the printable resin includes a polymerization catalyst. In some embodiments, the polymerization catalyst includes a tin catalyst, a platinum catalyst, a rhodium catalyst, a titanium catalyst, a silicon catalyst, a palladium catalyst, a metal triflate catalyst, a boron catalyst, a bismuth catalyst, or any combination thereof. Non-limiting examples of titanium catalysts include di-n-butyl butoxytin chloride, di-n-butyl diacetoxytin, di-n-butyl dilauryl tin, dimethyl dineodecanoate tin, dioctyl dilauryl tin, tetramethyl tin, and dioctyl bis(2-ethylhexyl maleate) tin. Non-limiting examples of platinum catalysts include platinum divinyltetramethyldisiloxane complex, platinum cyclovinylmethylsiloxane complex, platinum octanal complex, and platinum carbonyl cyclovinylmethylsiloxane complex. Non-limiting examples of rhodium catalysts include tri(dibutyl sulfide) rhodium trichloride. Non-limiting examples of titanium catalysts include titanium isopropoxide, 2-ethyl titanium oxide, triisopropoxide titanium chloride, titanium ethoxide, and titanium diisopropoxide bis(ethyl acetoacetate). Non-limiting examples of silicon catalysts include ammonium tetramethylsiloxane and tetramethylsilylmethyl trifluoromethanesulfonate. Non-limiting examples of palladium catalysts include tetrakis(triphenylphosphine)palladium(0). Non-limiting examples of metal trifluoromethanesulfonate catalysts include scandium trifluoromethanesulfonate, lanthanum trifluoromethanesulfonate, and ytterbium trifluoromethanesulfonate. Non-limiting examples of boron catalysts include tris(pentafluorophenyl)boron. Non-limiting examples of bismuth catalysts include bismuth zinc neodecanoate, bismuth 2-ethylhexanoate, metal carboxylates of bismuth and zinc, and metal carboxylates of bismuth and zirconium.

[0305] In some embodiments, the printable resin includes an inhibitor to stabilize the composition and prevent premature polymerization. In some embodiments, the inhibitor is a photoinhibitor (e.g., oxygen). In some embodiments, the inhibitor is a phenolic compound (e.g., BHT). In some embodiments, the inhibitor is a stable free radical (e.g., 2,2,4,4-tetramethylpiperidinyl-1-oxyl free radical, 2,2-diphenyl-1-picrylhydrazyl free radical, galvinoxyl free radical, or triphenylmethyl free radical). In some embodiments, there is more than one inhibitor in the resin. In some embodiments, the inhibitor acts as a free radical scavenger. In certain embodiments, the inhibitor is an antioxidant, hindered amine light stabilizer (HAL), hindered phenol, or inactivated free radical (e.g., peroxy compound). In some embodiments, the polymerization inhibitor is selected from 4-tert-butylcatechol, tert-butylhydroquinone, 1,4-benzoquinone, 6-tert-butyl-2,4-dimethylphenol, 2-tert-butyl-1,4-benzoquinone, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butylphenol, 1,1-diphenyl-2-picrylhydrazyl free radical, hydroquinone, 4-methoxyphenol, phenothiazine, any derivatives thereof, and any combination thereof.

[0306] In some embodiments, the printable resin includes a light blocker to dissipate UV radiation. In some embodiments, the light blocker absorbs a specific UV energy value and / or range. In some embodiments, the light blocker is a UV light absorber, a pigment, a color masterbatch, or an IR light absorber. In some embodiments, the light blocker includes a benzotriazole (e.g., 2-(2'-hydroxy-phenylbenzotriazole), a hydroxyphenyl triazine, an oxanilide, a benzophenone, or a combination thereof.

[0307] In some embodiments, the printable resin includes a filler. In some embodiments, the filler includes calcium carbonate (i.e., chalk), kaolin, metakaolinite, kaolinite derivatives, magnesium hydroxide (i.e., talc), calcium silicate (i.e., wollastonite), glass fillers (e.g., glass beads, short glass fibers, or long glass fibers), nanofillers (e.g., nanoplates, nanofibers, or nanoparticles), silica fillers (e.g., mica, silica gel, fumed silica, or precipitated silica), carbon black, dolomite, barium sulfate, ATH Al(OH)3, MDH Mg(OH)2, diatomaceous earth, magnetite, halloysite, zinc oxide, titanium dioxide, cellulose, lignin, carbon fillers (e.g., chopped carbon fibers or carbon fibers), derivatives thereof, or combinations thereof.

[0308] In some embodiments, the printable resin comprises a pigment, a dye, or a combination thereof. Pigments are typically suspended solids that may be insoluble in the resin. Dyes are typically dissolved in the printable resin. In some embodiments, the pigment comprises an inorganic pigment. In some embodiments, the inorganic pigment includes iron oxide, barium sulfide, zinc oxide, antimony trioxide, yellow iron oxide, red iron oxide, ammonium ferrocyanide, chrome yellow, carbon black, or aluminum flakes. In some embodiments, the pigment comprises an organic pigment. In some embodiments, the organic pigment comprises an azo pigment, an anthraquinone pigment, a copper phthalocyanine (CPC) pigment (e.g., phthalocyanine blue or phthalocyanine green), or a combination thereof. In some embodiments, the dye comprises an azo dye (e.g., a diarylide or Sudan dye), an anthraquinone (e.g., Oil Blue A or Disperse Red 11), or a combination thereof.

[0309] In some embodiments, the printable resin includes a surface energy modifier. In some embodiments, the surface energy modifier can aid in the process of releasing the polymer from the mold. In some embodiments, the surface energy modifier can act as a defoaming agent. In some embodiments, the surface energy modifier includes a defoaming agent, a degassing agent, a hydrophobic agent, a leveling agent, a wetting agent, or an agent that adjusts the flow properties of the printable resin. In some embodiments, the surface energy modifier includes an alkoxylated surfactant, an organosilicon surfactant, a sulfosuccinate, a fluorinated polyacrylate, a fluoropolymer, a polysiloxane, a star polymer, an organically modified polysiloxane, or any combination thereof.

[0310] In some embodiments, the printable resin includes a plasticizer. The plasticizer can be a non-volatile material that can reduce interactions between polymer chains, which can lower the glass transition temperature, melt viscosity, and elastic modulus. In some embodiments, the plasticizer includes a dicarboxylate plasticizer, a tricarboxylate plasticizer, a trimellitate, an adipate, a sebacate, a maleate, or a bio-based plasticizer. In some embodiments, the plasticizer comprises a dicarboxylate or tricarboxylate comprising a dibasic ester, a phthalate, bis(2-ethylhexyl) phthalate (DEHP), bis(2-propylheptyl) phthalate (DPHP), diisononyl phthalate (DINP), di-n-butyl phthalate (DBP), butylbenzyl phthalate (BBzP), diisodecyl phthalate (DIDP), dioctyl phthalate (DOP), diisooctyl phthalate (DIOP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), di-n-hexyl phthalate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises a trimellitic acid ester, including trimethyl trimellitate (TMTM), tri(2-ethylhexyl) trimellitate (TEHTM), tri(n-octyl, n-decyl) trimellitate (ATM), tri(heptyl, nonyl) trimellitate (LTM), n-octyl trimellitate (OTM), trioctyl trimellitate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises an adipate ester, including bis(2-ethylhexyl) adipate (DEHA), dimethyl adipate (DMAD), monomethyl adipate (MMAD), dioctyl adipate (DOA), bis[2-(2-butoxyethoxy)ethyl] adipate, dibutyl adipate, diisobutyl adipate, diisodecyl adipate, derivatives thereof, or combinations thereof. In some embodiments, plasticizer comprises sebacic acid ester, including dibutyl sebacate (DBS), bis (2-ethylhexyl) sebacate, diethyl sebacate, dimethyl sebacate, its derivative or its combination.In some embodiments, plasticizer comprises maleate, including bis (2-ethylhexyl) maleate, dibutyl maleate, diisobutyl maleate, its derivative or its combination.In some embodiments, plasticizer comprises bio-based plasticizer, including acetylated monoglyceride, alkyl citrate, methyl ricinoleate or green plasticizer.In some embodiments, alkyl citrate is selected from triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate, trioctyl citrate, acetyl trioctyl citrate, trihexyl citrate, acetyl trihexyl citrate, butyryl trihexyl citrate, trimethyl citrate, its derivative or its combination. In some embodiments, the green plasticizer is selected from epoxidized soybean oil, epoxidized vegetable oil, epoxidized esters of soybean oil, derivatives thereof, or combinations thereof.In some embodiments, the plasticizer comprises azelate, a benzoate (e.g., sucrose benzoate), a terephthalate (e.g., dioctyl terephthalate), diisononyl 1,2-cyclohexanedicarboxylate, phenyl alkylsulfonates, sulfonamides (e.g., N-ethyltoluenesulfonamide, N-(2-hydroxypropyl)benzenesulfonamide, N-(n-butyl)benzenesulfonamide), an organophosphate (e.g., tricresyl phosphate or tributyl phosphate), a glycol (e.g., triethylene glycol dihexanoate or tetraethylene glycol diheptanoate), a polyether, a polymeric plasticizer, polybutene, a derivative thereof, or a combination thereof.

[0311] In some embodiments, the printable resin comprises a solvent. In some embodiments, the solvent comprises a non-polar solvent. In certain embodiments, the non-polar solvent comprises pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1,4-dioxane, chloroform, ether, dichloromethane, derivatives thereof, or combinations thereof. In some embodiments, the solvent comprises a polar aprotic solvent. In certain embodiments, the polar aprotic solvent comprises tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, acetonitrile, DMSO, propylene carbonate, derivatives thereof, or combinations thereof. In some embodiments, the solvent comprises a polar protic solvent. In certain embodiments, the polar protic solvent comprises formic acid, n-butanol, isopropanol, n-propanol, tert-butanol, ethanol, methanol, acetic acid, water, derivatives thereof, or combinations thereof.

[0312] In some embodiments, the printable resin comprises a biologically interesting chemical. In some embodiments, the biologically interesting chemical comprises a hormone, an enzyme, an active pharmaceutical ingredient, an antibody, a protein, a drug, or any combination thereof. In some embodiments, the biologically interesting chemical comprises a pharmaceutical composition, a chemical, a gene, a polypeptide, an enzyme, a biomarker, a dye, a compliance indicator, an antibiotic, an analgesic, a medical-grade drug, a chemical reagent, a bioactive agent, an antimicrobial agent, an antibiotic, an anti-inflammatory agent, an immunosuppressant, an immunostimulant, a dentin desensitizer, an odor masking agent, an immunological agent, an anesthetic, a nutrient, an antioxidant, a lipopolysaccharide complexing agent, or a peroxide.

[0313] In some embodiments, the added components (i.e., thermal initiators, polymerization catalysts, polymerization inhibitors, light blockers, plasticizers, solvents, surface energy modifiers, pigments, dyes, fillers, or chemicals of biological interest) are functionalized to enable them to be incorporated into the polymer network, thereby making them less susceptible to extraction from the final cured material. In certain embodiments, thermal initiators, polymerization catalysts, polymerization inhibitors, light blockers, plasticizers, surface energy modifiers, pigments, dyes, and / or fillers are functionalized to facilitate their incorporation into the cured polymer material. As used herein, a polymer network may refer to a polymer composition comprising a plurality of polymer chains, wherein a majority (e.g., ≥80%) and optionally all of the polymer chains are interconnected by, for example, weak covalent crosslinks to form a single polymer composition. In one embodiment, a radiopaque polymer in the form of a crosslinked network is provided, wherein at least some of the crosslinks in the network structure are formed by covalent bonds.

[0314] In some embodiments, the polymeric material formed from the resin has a low level of extractables (e.g., unreacted monomers from the photocurable resin). The amount of extractables can be determined by the weight loss after soaking the polymeric material in water for 1 week, in ethanol for 48 hours, or in hexane for 48 hours. A general experiment for determining the amount of extractables includes the following steps: (i) weighing a dry sample of the polymeric material; (ii) soaking the sample in a solvent for a period of time at a given temperature (e.g., 25° C.); (iii) refreshing the solvent until the extraction is complete; (iv) drying the sample in an oven; (v) weighing the extracted sample; and (vi) calculating the weight loss. In some embodiments, the polymeric material formed from the resin has less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.75 wt%, less than 0.5 wt%, or less than 0.25 wt% extractables.

[0315] In some embodiments, multiple weak covalent bonds are used so that they cover a range of different bond dissociation energies. As a non-limiting example, in a single material of the present invention, some weak covalent bonds have a bond dissociation energy of 280 kJ / mol, some have a bond dissociation energy of 250 kJ / mol, some have a bond dissociation energy of 200 kJ / mol, and some have a bond dissociation energy of 80 kJ / mol. A material having multiple different weak covalent bond dissociation energies provides a material having multiple different yield strengths within the material depending on the concentration of different weak covalent chains.

[0316] The printable resins disclosed herein can be formed from polymeric materials comprising weak crosslinks, strong crosslinks, polymer chains, or ring monomers, which can be used alone or in combination. In some embodiments, printable resin compositions comprising weak crosslinks, strong crosslinks, polymer chains, or ring monomers, alone or in combination, also comprise the printable resin properties disclosed herein.

[0317] E. Methods for producing polymer materials

[0318] In some embodiments, the present disclosure provides a method for producing a polymeric material as described herein generated from a printable resin as further described herein. In some embodiments, the method comprises the following steps:

[0319] providing a printable resin as further disclosed herein; and

[0320] The printable resin is cured, wherein the curing includes exposure to light, thereby forming a cured polymer material.

[0321] In some embodiments, the method further comprises the step of manufacturing the device using an additive manufacturing device, wherein the additive manufacturing device facilitates curing. In some embodiments, curing of the printable resin produces a polymeric material. In certain embodiments, curing of the printable resin using the additive manufacturing device produces the polymeric material. In some embodiments, the method further comprises the step of cleaning the polymeric material. In certain embodiments, cleaning the polymeric material comprises washing and / or rinsing the polymeric material with a solvent that removes monomers and undesirable impurities from the polymeric material.

[0322] In some embodiments, the printable resin is curable and has a melting point <120°C so as to be liquid at temperatures typically used for currently available additive manufacturing technologies and, therefore, processable. The printable resin comprises at least one photopolymerization initiator (i.e., photoinitiator) and can be heated to a predetermined elevated process temperature of 50°C to 120°C, such as 90°C to 120°C, and then irradiated with light of a suitable wavelength to be absorbed by the photoinitiator, thereby causing activation of the photoinitiator to initiate polymerization of the printable resin to obtain a weakly covalently cross-linked polymer material.

[0323] In some embodiments, the method disclosed herein is part of a high-temperature photolithography-based photopolymerization process, wherein the curable composition (i.e., printable resin) comprises at least one photopolymerization initiator and is heated, which makes the high-temperature photolithography-based photopolymerization process more preferably an additive manufacturing process, most preferably a 3D printing process. The method according to the present disclosure provides the possibility of quickly and conveniently producing devices (e.g., orthodontic appliances) by additive manufacturing (e.g., 3D printing) using the printable resin disclosed herein.

[0324] Photopolymerization occurs when a suitable formulation (e.g., a printable resin disclosed herein) is exposed to radiation (e.g., UV or visible light) of sufficient power and wavelength to initiate polymerization. The wavelength and / or power of the radiation used to initiate polymerization may depend on the photoinitiator used. As used herein, "light" includes any wavelength and power capable of initiating polymerization. Certain wavelengths of light include ultraviolet (UV), visible, or infrared. UV light sources include UVA (wavelength of about 400 nanometers (nm) to about 320 nm), UVB (about 320 nm to about 290 nm), or UVC (about 290 nm to about 100 nm). Any suitable source can be used, including a laser source. The source can be broadband or narrowband, or a combination thereof. The light source can provide continuous light, pulsed light, or both continuous and pulsed light during the process. The length of time the system is exposed to the light and the intensity of the light can be varied to determine the ideal reaction conditions.

[0325] In some embodiments, the methods disclosed herein use additive manufacturing to produce devices comprising polymeric materials. In certain embodiments, the methods disclosed herein use additive manufacturing to produce devices consisting essentially of polymeric materials. Additive manufacturing includes a variety of technologies that can directly manufacture three-dimensional objects from digital models through additive manufacturing processes. In some aspects, continuous layers of material are deposited and "cured in place". Various technologies for additive manufacturing are known in the art, including selective laser sintering (SLS), fused deposition modeling (FDM), and injection or extrusion. In many embodiments, selective laser sintering involves using a laser beam to selectively melt and fuse layers of powdered material according to the desired cross-sectional shape to establish the geometry of the object. In many embodiments, fused deposition modeling involves melting and selectively depositing filaments of thermoplastic polymers in a layer-by-layer manner to form an object. In yet another example, 3D printing can be used to manufacture the devices herein. In many embodiments, 3D printing involves spraying or extruding one or more materials (e.g., resins disclosed herein) onto a build surface to form continuous layers of the geometry of the object. In some embodiments, the resins described herein can be used for inkjet or coating applications. Polymer materials can also be made by a "barrel" process, in which light is used to selectively cure a barrel or reservoir of curable resin (e.g., the resins disclosed herein). Each layer of the curable resin can be selectively exposed to light in a single exposure or by scanning the light beam across the entire layer. Specific techniques include stereolithography (SLA), digital light processing (DLP), holographic projection, and two-photon induced photopolymerization (TPIP).

[0326] In some embodiments, method disclosed herein uses continuous direct manufacturing to produce the device comprising polymeric material. In certain embodiments, method disclosed herein uses continuous direct manufacturing to produce the device consisting essentially of polymeric material. Non-limiting exemplary direct manufacturing process can realize the continuous construction of object geometry by the continuous movement (for example, along vertical direction or Z direction) of building platform during irradiation stage, so that the hardening depth of irradiated photopolymer (for example, irradiated resin, hardens during the formation of polymeric material) is controlled by moving speed. Therefore, the continuous polymerization (for example, resin is polymerized into polymeric material) of material can be realized on the building surface. Such method is described in U.S. Patent number 7,892,474 and U.S. Patent number 10,162,264, the disclosure of which is incorporated herein by reference in its entirety. In another example, continuous direct manufacturing method utilizes " spiral lithography (heliolithography) " method, wherein while continuously rotating and raising building platform, utilize focused radiation to solidify liquid resin (for example, printable resin). Therefore, object geometry can be continuously built along spiral construction path. Such methods are described in U.S. Patent Publication No. 2014 / 0265034, the disclosure of which is incorporated herein by reference in its entirety. Continuous liquid interface production of 3D objects has also been reported (J. Tumbleston et al., Science, 2015, 347(6228), pp 1349-1352), the entire contents of which are incorporated herein by reference to describe such methods. Another example of a continuous direct manufacturing method may include extruding a material consisting of a polymer material surrounding a solid strand. The material may be extruded along a continuous three-dimensional path to form an object. Such methods are described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0327] In some embodiments, the method disclosed herein uses high temperature lithography to produce a device comprising a polymer material. In certain embodiments, the method disclosed herein uses high temperature lithography to produce a device consisting essentially of a polymer material. As used herein, "high temperature lithography" may refer to any lithography-based photopolymerization process that involves heating one or more photopolymerizable materials (e.g., curable resins disclosed herein). Heating can reduce the viscosity of one or more photopolymerizable materials before and / or during curing. Non-limiting examples of high temperature lithography processes include those described in WO 2015 / 075094, WO2016 / 078838, and WO 2018 / 032022. In certain embodiments, high temperature lithography may involve heating the material to a temperature of 50°C-120°C, such as 90°C-120°C, 100°C-120°C, 105°C-115°C, 108°C-110°C, etc. The material may be heated to a temperature higher than 120°C. Note that other ranges may be used without departing from the scope and essence of the inventive concepts described herein.

[0328] In another embodiment, the method disclosed herein includes a continuous direct manufacturing step. The continuous direct manufacturing step may involve extruding a material consisting of a curable liquid material (e.g., a printable resin) surrounding a solid strand. The liquid material can be extruded along a continuous three-dimensional path to form an object or device. Such methods are described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0329] In some preferred embodiments, the methods disclosed herein further comprise fabricating the object from the polymeric material. In certain embodiments, fabricating the object comprises additive manufacturing. In some embodiments, fabricating the object from the polymeric material comprises printing with a 3D printer. In some embodiments, fabricating the object from the polymeric material comprises digital light projection. In certain embodiments, fabricating the object from the polymeric material comprises using thermal lithography.

[0330] In some embodiments, the object is an orthodontic appliance. In some embodiments, the orthodontic appliance is an aligner, expander, or spacer. In some embodiments, the orthodontic appliance includes a plurality of tooth sockets configured to reposition teeth from a first configuration toward a second configuration. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration toward a target configuration, optionally according to a treatment plan.

[0331] F. Devices using polymer materials

[0332] In some embodiments, the present disclosure provides devices comprising a polymeric material generated from a printable resin as further described herein. In some embodiments, the polymeric material is used to manufacture a device intended to be placed in a person's mouth. For example, such a device may be an aligner that helps move teeth into a new position. In some embodiments, the device may be a retainer that helps prevent teeth from moving into a new position. In some embodiments, the device may be used to expand the palate, move the mandible, or prevent a person from snoring.

[0333] In some embodiments, the present disclosure provides a method for producing a device described herein, the device comprising a polymeric material. In some embodiments, the method includes a step of molding the printable resin into a desired shape before the step of curing the printable resin, thereby generating a polymeric material having the desired shape. In some embodiments, the method includes a step of molding the printable resin into a desired shape during the step of curing the printable resin, thereby generating a polymeric material having the desired shape. In some embodiments, the method includes a step of curing the printable resin, thereby forming the polymeric material, and then molding the polymeric material into the desired shape. In some embodiments, the desired shape is an orthodontic appliance. In some embodiments, the desired shape is a device and / or object as disclosed herein. In some embodiments, the molding step includes extrusion, sheet production, film production, melt spinning, coating, injection molding, compression and transfer molding, blow molding, rotational blow molding, thermoforming, casting, or a combination thereof.

[0334] Exemplary embodiments of devices that can be cured using the materials disclosed herein include dental appliances for humans. In some embodiments, such devices can be used as treatment systems for providing orthodontic treatment.

[0335] In certain aspects, the present disclosure provides a method for manufacturing an orthodontic appliance comprising a polymeric material as described herein, the method comprising providing a printable resin as further described herein; and manufacturing the polymeric material by a direct or additive manufacturing process. The printable resin may be exposed to light during the direct or additive manufacturing process. The method may further comprise an additional curing step after manufacturing the polymeric material.

[0336] In certain aspects, the present disclosure provides an orthodontic appliance comprising a polymeric material as further described herein. The orthodontic appliance can be an aligner, an expander, or a spacer. In some embodiments, the orthodontic appliance includes a plurality of tooth receiving cavities configured to reposition teeth from a first configuration toward a second configuration. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration, optionally according to a treatment plan. As used herein, "multiple teeth" encompasses two or more teeth.

[0337] In many embodiments, the one or more posterior teeth include one or more of molars, premolars, or canines, and the one or more anterior teeth include one or more of central incisors, lateral incisors, canines, first bicuspids, or second bicuspids.

[0338] Curable resins and cured polymeric materials according to the present disclosure exhibit advantageous thermomechanical properties and can be used as orthodontic appliances, for example, for moving one or more teeth.

[0339] Embodiments disclosed herein can be used to couple one or more groups of teeth to each other. The one or more groups of teeth can include a first group of one or more anterior teeth and a second group of one or more posterior teeth. The first group of teeth can be coupled to the second group of teeth via a polymer shell appliance disclosed herein.

[0340] The embodiments disclosed herein are well suited for moving one or more teeth of a first set of one or more teeth or moving one or more teeth of a second set of one or more teeth, and combinations thereof.

[0341] The embodiments disclosed herein are well suited for combination with one or more known commercially available tooth movement components (e.g., attachments and polymer shell appliances). In many embodiments, the appliance and one or more attachments are configured to move one or more teeth along a tooth movement vector comprising six degrees of freedom, three of which are rotational and three of which are translational.

[0342] The present disclosure provides orthodontic systems and related methods for designing and providing improved or more effective tooth movement systems to induce desired tooth movement and / or reposition teeth into a desired arrangement.

[0343] Although reference is made to instruments comprising polymer shell instruments, the embodiments disclosed herein are well suited for use with many tooth-receiving instruments (e.g., instruments without one or more polymers or shells). The instrument can be manufactured using one or more of a variety of materials (e.g., metal, glass, reinforcing fibers, carbon fibers, composite materials, reinforced composite materials, aluminum, biomaterials, and combinations thereof). In some cases, the reinforced composite material can include, for example, a polymer matrix reinforced with ceramic or metal particles. The instrument can be formed in a variety of ways, for example, by thermoforming as described herein or by direct manufacturing. Alternatively or in combination, the instrument can be manufactured by machining, for example, by computer numerical control machining an instrument manufactured from a piece of material. Preferably, the instrument is manufactured using a curable resin according to the present disclosure.

[0344] Turning now to the drawings, wherein like numerals represent like elements throughout the various views, Figure 1AAn exemplary tooth repositioning appliance or aligner 100 is shown that can be worn by a patient to achieve progressive repositioning of a single tooth 102 in the mandible and includes a cured polymer material disclosed herein. The appliance may include a shell (e.g., a continuous polymer shell or a segmented shell) having a tooth receptacle that receives and elastically repositions the tooth. The appliance or one or more portions thereof may be indirectly manufactured using a physical model of the tooth. For example, an appliance (e.g., a polymer appliance) may be formed using a physical model of the tooth and a sheet of a suitable layer of polymer material. In some embodiments, the physical appliance is manufactured directly from a digital model of the appliance, for example using rapid prototyping techniques. The appliance can be fitted over all or fewer than all teeth present in the upper or lower jaw. The appliance can be specifically designed to accommodate the patient's teeth (e.g., the topography of the tooth receptacle matches the topography of the patient's teeth) and can be manufactured based on a positive or negative model of the patient's teeth generated by pressing, scanning, etc. Alternatively, the appliance can be a general appliance configured to receive teeth, but it is not necessarily shaped to match the topography of the patient's teeth. In some cases, only specific teeth received by the appliance are repositioned by the appliance, while other teeth may provide a base or anchoring area for holding the appliance in place while the appliance applies a force to the tooth or teeth to be repositioned. In some cases, at some point during treatment, a portion, most, or even all of the teeth are repositioned. The moved teeth may also serve as a base or anchor for securing the appliance while the patient wears the appliance. Typically, no wire or other device will be provided to hold the appliance in place on the tooth. However, in some cases, it may be desirable or necessary to provide a separate attachment or other anchoring element 104 on the tooth 102 and a corresponding socket or hole 106 in the appliance 100 so that the appliance can apply a selected force to the tooth. In various patents and patent applications assigned to Align Technology, Inc., including, for example, U.S. Patent Nos. 6,450,807 and 5,975,893, and on the company's website, which can be accessed on the World Wide Web (e.g., see the URL "invisalign.com"), including Examples of tooth-mounted attachments suitable for use with orthodontic appliances are also described in patents and patent applications assigned to Align Technology, Inc., including, for example, US Pat. Nos. 6,309,215 and 6,830,450.

[0345] Figure 1BA tooth repositioning system 110 is shown that includes a plurality of appliances 112, 114, 116. Any of the appliances described herein can be designed and / or provided as part of a set of a plurality of appliances for use in a tooth repositioning system. Each appliance can be configured to provide a tooth receiving cavity with a geometry corresponding to an intermediate or final tooth arrangement for which the appliance is intended. The patient's teeth can be progressively repositioned from an initial tooth arrangement to a target tooth arrangement by placing a series of progressively position-adjusting appliances on the patient's teeth. For example, the tooth repositioning system 110 can include a first appliance 112 corresponding to an initial tooth arrangement, one or more intermediate appliances 114 corresponding to one or more intermediate arrangements, and a final appliance 116 corresponding to a target arrangement. The target tooth arrangement can be the planned final tooth arrangement selected for the patient's teeth at the conclusion of all planned orthodontic treatment. Alternatively, the target arrangement can be one of several intermediate arrangements of the patient's teeth during orthodontic treatment, which can include a variety of different treatment plans, including but not limited to situations where surgery is recommended, interproximal surface removal (IPR) is appropriate, a progress review is planned, the anchor position is optimal, palate expansion is required, dental restorations (e.g., inlays, onlays, crowns, bridges, implants, veneers, etc.) are involved, etc. Thus, it will be understood that the target tooth arrangement can be any planned resulting arrangement of the patient's teeth following one or more progressive repositioning stages. Similarly, the initial tooth arrangement can be any initial arrangement of the patient's teeth followed by one or more progressive repositioning stages.

[0346] Figure 1CAn orthodontic treatment method 150 using multiple appliances according to an embodiment is shown. Method 150 can be implemented using any appliance or appliance group described herein. In step 160, a first orthodontic appliance is applied to the patient's teeth so as to reposition the teeth from the first tooth arrangement to the second tooth arrangement. In step 170, a second orthodontic appliance is applied to the patient's teeth so as to reposition the teeth from the second tooth arrangement to the third tooth arrangement. If necessary, method 150 can be repeated using any suitable number and combination of sequential appliances so as to progressively reposition the patient's teeth from the initial arrangement to the target arrangement. Appliances can be produced all at the same stage, or in groups or batches (e.g., at the beginning of a stage of treatment), or appliances can be produced one at a time, and the patient can wear each appliance until the pressure of each appliance on the teeth is no longer felt, or until the maximum tooth movement expressed in a given stage is reached. Before a patient wears any of the multiple appliances, multiple different appliances (e.g., a group) can be designed and even manufactured. After wearing the appliance for an appropriate period of time, the patient can replace the current appliance with the next appliance in the series until there are no more appliances. The appliances are typically not fixed to the teeth, and the patient can place and replace the appliances at any time during the procedure (e.g., patient-removable appliances). The final appliance or multiple appliances in a series may have one or more geometries selected to overcorrect the dental arrangement. For example, the geometry of one or more appliances may (if fully implemented) move a single tooth outside of the dental arrangement that has been selected as the "final". Such overcorrection may be desirable to offset potential relapse after the repositioning method is terminated (e.g., allowing a single tooth to move back to its pre-correction position). Overcorrection may also help to speed up the correction (e.g., an appliance with a geometry that is positioned beyond a desired intermediate or final position may move a single tooth toward that position at a greater rate). In this case, use of the appliance may be terminated before the tooth reaches the position defined by the appliance. In addition, overcorrection may be intentionally performed to compensate for any inaccuracies or limitations of the appliance.

[0347] The various embodiments of the orthodontic appliances presented herein can be manufactured in a variety of ways. In some embodiments, the orthodontic appliances herein (or portions thereof) can be manufactured using direct manufacturing, such as additive manufacturing techniques (also referred to herein as "3D printing") or subtractive manufacturing techniques (e.g., milling). In some embodiments, direct manufacturing involves forming an object (e.g., an orthodontic appliance or a portion thereof) without using a physical template (e.g., a mold, a mask, etc.) to define the geometry of the object. Additive manufacturing techniques can be categorized as follows: (1) vat photopolymerization (e.g., stereolithography), in which an object is constructed layer by layer from a vat of liquid photopolymerizable resin; (2) material jetting, in which material is jetted onto a build platform using a continuous or drop-on-demand (DOD) process; (3) binder jetting, in which alternating layers of a build material (e.g., a powder-based material) and a binder material (e.g., a liquid binder) are deposited by a print head; (4) fused deposition modeling (FDM), in which material is drawn through a nozzle, heated, and deposited layer by layer; (5) powder bed fusion, including but not limited to direct metal laser sintering (DMLS), electron beam melting (EBM), selective heat sintering (SHS), selective laser melting (SLM), and selective laser sintering (SLS); (6) sheet lamination, including but not limited to laminated object manufacturing (LOM) and ultrasonic additive manufacturing (UAM); and (7) directed energy deposition, including but not limited to laser engineered mesh forming, directed light manufacturing, direct metal deposition, and 3D laser cladding. For example, stereolithography can be used to directly manufacture one or more devices described herein. In some embodiments, stereolithography involves using light (e.g., ultraviolet light) to selectively polymerize a photosensitive resin (e.g., a photopolymer) according to a desired cross-sectional shape. By sequentially polymerizing multiple object cross-sections, the object geometry can be constructed in a layer-by-layer manner. As another example, the apparatus herein can be directly manufactured using selective laser sintering. In some embodiments, selective laser sintering involves using a laser beam to selectively melt and fuse layers of powdered material according to a desired cross-sectional shape to construct the geometry of the object. As yet another example, the apparatus herein can be directly manufactured by fused deposition modeling. In some embodiments, fused deposition modeling involves melting and selectively depositing filaments of thermoplastic polymers in a layer-by-layer manner to form an object. In yet another example, the apparatus herein can be directly manufactured using material jetting. In some embodiments, material jetting involves spraying or extruding one or more materials onto a build surface to form continuous layers of the object geometry.

[0348] Alternatively or in combination, some embodiments of the devices herein (or portions thereof) can be produced using indirect manufacturing techniques, such as by thermoforming on a male or female mold. Indirect manufacturing of orthodontic devices can involve producing a male or female mold of the patient's dentition in the target arrangement (e.g., by rapid prototyping, milling, etc.) and thermoforming one or more layers of material onto the mold to create the device housing.

[0349] In some embodiments, the direct manufacturing method provided herein builds object geometry in a layer-by-layer manner, wherein continuous layers are formed in discontinuous construction steps. Alternatively or in combination, a direct manufacturing method that allows continuous construction of object geometry can be used, referred to herein as "continuous direct manufacturing". Various types of continuous direct manufacturing methods can be used. As an example, in some embodiments, the apparatus herein is manufactured using "continuous liquid interface printing", wherein a gradient of partially cured resin is formed between the construction surface of the object and the "dead zone" that suppresses polymerization, and an object is continuously built from a reservoir of a photopolymerizable resin. In some embodiments, a semipermeable membrane is used to control the transport of a photopolymerization inhibitor (such as oxygen) into the dead zone to form a polymerization gradient. Continuous liquid interface printing can achieve a manufacturing speed about 25 times to about 100 times faster than other direct preparation methods, and can achieve a speed about 1000 times faster by combining a cooling system. Continuous liquid interface printing is described in U.S. Patent Publication Nos. 2015 / 0097315, 2015 / 0097316, and 2015 / 0102532, the disclosures of each of which are incorporated herein by reference in their entirety.

[0350] As another example, a continuous direct manufacturing method can achieve continuous construction of the object geometry by continuously moving the build platform (e.g., in the vertical or Z direction) during the irradiation phase, so that the hardening depth of the irradiated photopolymer is controlled by the movement speed. Thus, continuous polymerization of the material on the build surface can be achieved. Such a method is described in U.S. Patent No. 7,892,474, the disclosure of which is incorporated herein by reference in its entirety.

[0351] In another example, a continuous direct manufacturing method can include extruding a composite material composed of a curable liquid material surrounding a solid strand. The composite material can be extruded along a continuous three-dimensional path to form an object. Such a method is described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0352] In yet another example, a continuous direct manufacturing method utilizes a "spiral lithography" approach, in which a liquid photopolymer is cured using focused radiation while the build platform is continuously rotated and raised. Thus, object geometries can be continuously built along a spiral build path. Such a method is described in U.S. Patent Publication No. 2014 / 0265034, the disclosure of which is incorporated herein by reference in its entirety.

[0353] Machine parameters may include curing parameters. For digital light processing (DLP)-based curing systems, curing parameters may include power, curing time, and / or grayscale across the image. For laser-based curing systems, curing parameters may include power, speed, beam size, beam shape, and / or beam power distribution. For printing systems, curing parameters may include material droplet size, viscosity, and / or curing power. As part of process control for the manufacturing machine, these machine parameters may be monitored and adjusted regularly (e.g., some parameters every 1-x layers and some parameters after each build). Process control can be achieved by including sensors on the machine that measure power and other beam parameters every layer or every few seconds and automatically adjust them through a feedback loop. For DLP machines, depending on the stability of the system, grayscale may be measured and calibrated before, during, and / or at the end of each build, and / or at predetermined intervals (e.g., every n builds, once an hour, once a day, once a week, etc.). Furthermore, material properties and / or light characteristics may be provided to the manufacturing machine, which the machine process control module may use to adjust machine parameters (e.g., power, time, grayscale, etc.) to compensate for variability in material properties. By implementing process control on the manufacturing machines, reduced variability in device accuracy and residual stresses can be achieved.

[0354] Optionally, the direct manufacturing methods described herein allow for the manufacture of devices comprising multiple materials, referred to herein as "multi-material direct manufacturing". In some embodiments, the multi-material direct manufacturing method involves the simultaneous formation of an object from multiple materials in a single manufacturing step. For example, a multi-tip extrusion device can be used to selectively dispense multiple types of materials from different material supply sources in order to manufacture an object from a variety of different materials. Such a method is described in U.S. Patent No. 6,749,414, the disclosure of which is incorporated herein by reference in its entirety. Alternatively or in combination, the multi-material direct manufacturing method may involve the formation of an object from multiple materials in multiple sequential manufacturing steps. For example, a first portion of an object may be formed from a first material according to any direct manufacturing method herein, and then a second portion of the object may be formed from a second material according to the methods herein, and so on, until the entire object is formed.

[0355] Compared to other manufacturing methods, direct manufacturing can provide various advantages. For example, compared to indirect manufacturing, direct manufacturing allows orthodontic appliances to be produced without using any molds or templates for shaping the appliance, thereby reducing the number of manufacturing steps involved and improving the resolution and precision of the final appliance geometry. In addition, direct manufacturing allows precise control of the three-dimensional geometry of the appliance, such as appliance thickness. Complex structures and / or auxiliary components can be integrally formed as one piece with the appliance housing in a single manufacturing step, rather than being added to the housing in a separate manufacturing step. In some embodiments, direct manufacturing is used to produce appliance geometries that are difficult to produce using alternative manufacturing techniques, such as appliances with very small or fine features, complex geometries, undercuts, adjoining structures, shells with variable thickness, and / or internal structures (e.g., appliances that improve strength by reducing weight and material usage). For example, in some embodiments, the direct manufacturing method herein allows the manufacture of orthodontic appliances with feature sizes less than or equal to about 5 μm, or in the range of about 5 μm to about 50 μm, or in the range of about 20 μm to about 50 μm.

[0356] The direct manufacturing techniques described herein can be used to produce instruments having substantially isotropic material properties (e.g., substantially the same or similar strength in all directions). In some embodiments, the direct manufacturing methods herein allow for the production of orthodontic instruments whose strength varies no more than about 25%, about 20%, about 15%, about 10%, about 5%, about 1%, or about 0.5% along all directions. In some embodiments, the direct manufacturing techniques described herein can be used to produce instruments having substantially anisotropic material properties (e.g., having substantially different strengths in all directions). In some embodiments, the direct manufacturing techniques described herein can produce orthodontic instruments whose strength varies by greater than 10%, greater than 15%, greater than 20%, or greater than 25% along all directions but in a controlled manner. In addition, the direct manufacturing methods herein can be used to produce orthodontic instruments at a faster rate than other manufacturing techniques. In some embodiments, the direct manufacturing methods herein allow for the production of orthodontic appliances in time intervals of less than or equal to about 1 hour, about 30 minutes, about 25 minutes, about 20 minutes, about 15 minutes, about 10 minutes, about 5 minutes, about 4 minutes, about 3 minutes, about 2 minutes, about 1 minute, or about 30 seconds. Such manufacturing speeds allow for rapid "chair-side" production of custom appliances, for example, during routine appointments or checkups.

[0357] In some embodiments, the direct manufacturing methods described herein implement process controls on various machine parameters of the direct manufacturing system or apparatus to ensure that the resulting device is manufactured with high precision. Such precision can help ensure that the required force system is accurately transmitted to the teeth to effectively cause tooth movement. Process controls can be implemented to account for process variability caused by a variety of sources (e.g., material properties, machine parameters, environmental variables, and / or post-processing parameters).

[0358] Material properties may vary depending on the nature of the raw materials, the purity of the raw materials and / or process variables during the mixing of the raw materials. In many embodiments, the resin or other material used for direct manufacturing should be manufactured under strict process control to ensure that the variability of optical properties, material properties (e.g., viscosity, surface tension), physical properties (e.g., modulus, strength, elongation) and / or thermal properties (e.g., glass transition temperature, heat distortion temperature) is very small. Process control of the material manufacturing process can be achieved by screening the raw materials for physical properties and / or controlling the temperature, humidity and / or other process parameters during the mixing process. By implementing process control on the material manufacturing process, it is possible to achieve a reduction in the variability of process parameters and to make the material properties of each batch of materials more uniform. As further discussed herein, residual variability in material properties can be compensated by process control on the machine.

[0359] Machine parameters may include curing parameters. For curing systems based on digital light processing (DLP), curing parameters may include power, curing time, and / or grayscale of the entire image. For laser-based curing systems, curing parameters may include power, speed, beam size, beam shape, and / or power distribution of the beam. For printing systems, curing parameters may include material droplet size, viscosity, and / or curing power. As part of process control of the manufacturing machine, these machine parameters may be regularly monitored and adjusted (e.g., some parameters every 1-x layers and some parameters after each build). Process control can be achieved by including sensors on the machine that measure power and other beam parameters every layer or every few seconds and automatically adjust them through a feedback loop. For DLP machines, grayscale can be measured and calibrated at the end of each build. In addition, material properties and / or light characteristics may be provided to the manufacturing machine, which the machine process control module may use to adjust machine parameters (e.g., power, time, grayscale, etc.) to compensate for variability in material properties. By implementing process control on the manufacturing machine, variability in instrument accuracy and residual stress can be reduced.

[0360] In many embodiments, environmental variables (e.g., temperature, humidity, sunlight, or exposure to other energy / curing sources) are maintained within narrow ranges to reduce variability in device thickness and / or other properties. Optionally, machine parameters can be adjusted to compensate for environmental variables.

[0361] In many embodiments, the post-processing of the apparatus includes cleaning, post-curing and / or support removal processes. Related post-processing parameters may include the purity of the cleaning agent, cleaning pressure and / or temperature, cleaning time, post-curing energy and / or time, and / or the consistency of the support removal process. These parameters can be measured and adjusted as a part of a process control scheme. In addition, the physical properties of the apparatus can be changed by revising the post-processing parameters. Adjusting the post-processing machine parameters can provide another method to compensate for the variability of material properties and / or machine performance.

[0362] The configuration of orthodontic appliances herein can be determined according to a treatment plan for the patient (e.g., a treatment plan involving the continuous application of multiple appliances to progressively reposition teeth). Computer-based treatment plans and / or appliance manufacturing methods can be used to facilitate the design and manufacture of appliances. For example, one or more appliance assemblies described herein can be digitally designed and manufactured using computer-controlled manufacturing devices (e.g., computer numerical control (CNC) milling, computer-controlled rapid prototyping, such as 3D printing, etc.). The computer-based methods presented herein can improve the accuracy, flexibility, and convenience of appliance manufacturing.

[0363] Figure 2 A method 200 for designing an orthodontic appliance to be produced by direct manufacturing according to an embodiment is shown. The method 200 can be applied to any embodiment of the orthodontic appliance described herein. Some or all of the steps of the method 200 can be performed by any suitable data processing system or device (e.g., one or more processors configured with appropriate instructions).

[0364] In step 210, a movement path is determined for moving one or more teeth from an initial arrangement to a target arrangement. The initial arrangement can be determined from a mold or scan of the patient's teeth or oral tissue, for example, using wax bites, direct contact scanning, x-ray imaging, tomography, ultrasound imaging and other techniques to obtain information about the position and structure of the teeth, jaws, gums and other orthodontically relevant tissues. From the acquired data, a digital data set can be derived that represents the initial (e.g., before treatment) arrangement of the patient's teeth and other tissues. Optionally, the initial digital data set is processed to segment tissue components from each other. For example, a data structure can be generated that digitally represents a single crown. Advantageously, a digital model of the entire tooth can be generated, including measured or extrapolated hidden surface and root structures, as well as surrounding bone and soft tissue.

[0365] The target arrangement of teeth (e.g., the desired and expected end result of orthodontic treatment) can be received from the clinician in the form of a prescription, can be calculated based on basic orthodontic principles, and / or can be extrapolated from the clinical prescription. With the specification of the desired end position of the teeth and the digital representation of the teeth themselves, the final position and surface geometry of each tooth can be specified to form a complete model of the dental arrangement at the expected end of treatment.

[0366] With both an initial position and a target position for each tooth, a movement path can be defined for the movement of each tooth. In some embodiments, the movement path is configured to move the tooth in the quickest manner with the fewest round trips to get the tooth from its initial position to its desired target position. The tooth path can optionally be segmented, and the segments can be calculated so that the movement of each tooth within a segment remains within threshold limits for linear and rotational translation. In this way, the endpoints of each path segment can constitute a clinically feasible repositioning, and the collection of segment endpoints can constitute a clinically feasible sequence of tooth positions such that moving from one point to the next in the sequence does not result in tooth collision.

[0367] In step 220, a force system is determined to produce movement of one or more teeth along the movement path. The force system may include one or more forces and / or one or more torques. Different force systems may result in different types of tooth movement, such as tilting, translation, rotation, dislocation, depression, root movement, etc. Biomechanical principles, modeling techniques, force calculation / measurement techniques, etc., including knowledge and methods commonly used in orthodontics, can be used to determine the appropriate force system to be applied to the teeth to complete the tooth movement. When determining the force system to be applied, sources that may be considered include literature, force systems determined by experiments or virtual modeling, computer-based modeling, clinical experience, minimization of unnecessary forces, etc.

[0368] Determination of the force system can include constraints on allowable forces, such as allowable directions and magnitudes, and the desired movement to be caused by the applied forces. For example, when manufacturing a palatal expander, different movement strategies may be required for different patients. For example, since very young patients may not have fully formed sutures, the amount of force required to separate the palate may depend on the age of the patient. Therefore, in minors and other patients with incompletely closed palatal sutures, palatal expansion can be accomplished with less force. Slower palatal movement can also help bone grow to fill the expanded sutures. For other patients, more rapid expansion may be required, which can be achieved by applying greater forces. These requirements can be incorporated as needed into the selection of the structure and materials of the instrument; for example, by selecting a palatal expander that can apply greater forces to break the palatal sutures and / or cause rapid expansion of the palate. Subsequent instrument stages can be designed to apply different amounts of force, such as first applying a greater force to break the sutures and then applying a smaller force to keep the sutures apart or gradually expand the palate and / or arch.

[0369] Determination of the force system can also include modeling the patient's facial structures, such as the skeletal structure of the jaw and palate. For example, scan data of the palate and arch (e.g., X-ray data or 3D optical scan data) can be used to determine the parameters of the skeletal and muscular system of the patient's mouth, thereby determining the force sufficient to provide the desired expansion of the palate and / or arch. In some embodiments, the thickness and / or density of the middle suture of the palate can be measured or input by a treating professional. In other embodiments, the treating professional can select an appropriate treatment based on the patient's physiological characteristics. For example, the characteristics of the palate can also be evaluated based on factors such as the patient's age. For example, young, underage patients will generally require lower forces to expand the sutures than older patients because the sutures have not yet been fully formed.

[0370] In step 230, an arch or palatal expander design is determined for an orthodontic appliance arranged to generate a force system. A treatment or force application simulation environment can be used to determine the design, appliance geometry, material composition, and / or performance of the arch or palatal expander. The simulation environment can include, for example, a computer modeling system, a biomechanical system or device, or the like. Optionally, a digital model of the appliance and / or teeth, such as a finite element model, can be generated. The finite element model can be created using computer program application software available from various vendors. To create a solid geometric model, a computer-aided engineering (CAE) or computer-aided design (CAD) program can be used, such as the one provided by Autodesk, Inc. of San Rafael, CA. Software Products. To create finite element models and perform analyses thereon, program products from several vendors may be used, including the finite element analysis software package from ANSYS, Inc. of Canonsburg, PA, and the SIMULIA (Abaqus) software product from Dassault Systèmes of Waltham, MA.

[0371] Optionally, one or more arch or palatal expander designs can be selected for testing or force modeling. As described above, the desired tooth movement and the force system required or desired to cause the desired tooth movement can be identified. Using the simulation environment, candidate arch or palatal expander designs can be analyzed or modeled to determine the actual force system generated by using the candidate device. Optionally, one or more modifications can be made to the candidate device and further analyzed and force modeled as described, for example, to repeatedly determine the device design that produces the desired force system.

[0372] In step 240, instructions for manufacturing an orthodontic appliance incorporating the arch or palatal expander design are generated. The instructions can be configured to control a manufacturing system or device to produce an orthodontic appliance having a specified arch or palatal expander design. In some embodiments, the instructions are configured to manufacture the orthodontic appliance using direct manufacturing (e.g., stereolithography, selective laser sintering, fused deposition modeling, 3D printing, continuous direct manufacturing, multi-material direct manufacturing, etc.) according to the various methods provided herein. In alternative embodiments, the instructions can be configured to manufacture the appliance indirectly, such as by thermoforming.

[0373] Method 200 may include the additional steps of: 1) performing an intraoral scan of the patient's upper dental arch and palate to generate three-dimensional data of the palate and upper dental arch; and 2) determining a three-dimensional shape profile of the appliance to provide the clearance and tooth engagement structure as described herein.

[0374] Although the above steps illustrate a method 200 for designing an orthodontic appliance according to some embodiments, those skilled in the art will recognize variations based on the teachings described herein. Some steps may include substeps. Some of the steps may be repeated as needed. One or more steps of method 200 may be performed using any suitable manufacturing system or apparatus (e.g., the embodiments described herein). Some steps may be optional, and the order of the steps may be changed as needed.

[0375] Figure 3 A method 300 for digitally planning orthodontic treatment and / or designing or manufacturing an appliance, according to an embodiment, is shown. The method 300 can be applied to any treatment procedure described herein and can be performed by any suitable data processing system.

[0376] In step 310, a digital representation of a patient's teeth is received. The digital representation may include surface topography data of the patient's oral cavity (including teeth, gum tissue, etc.). The surface topography data may be generated by directly scanning the oral cavity, a physical model (positive or negative) of the oral cavity, or an impression of the oral cavity using a suitable scanning device (e.g., a handheld scanner, a desktop scanner, etc.).

[0377] In step 320, one or more treatment phases are generated based on the digital representation of the teeth. A treatment phase can be a progressive repositioning phase of an orthodontic treatment procedure designed to move one or more teeth of a patient from an initial tooth arrangement to a target tooth arrangement. For example, a treatment phase can be generated by determining an initial tooth arrangement indicated by the digital representation, determining a target tooth arrangement, and determining a movement path for one or more teeth in the initial arrangement required to achieve the target tooth arrangement. The movement path can be optimized based on minimizing the total distance moved, preventing inter-tooth collisions, avoiding more difficult tooth movements, or any other suitable criteria.

[0378] In step 330, at least one orthodontic appliance is manufactured based on the generated treatment phase. For example, a set of appliances can be manufactured, each appliance being shaped according to a specific tooth arrangement for a treatment phase, such that the patient can wear the appliances sequentially to progressively reposition the teeth from an initial arrangement to a target arrangement. The appliance set can include one or more of the orthodontic appliances described herein. Manufacturing the appliance may involve creating a digital model of the appliance for use as input to a computer-controlled manufacturing system. The appliance can be formed using direct manufacturing methods, indirect manufacturing methods, or a combination thereof, as desired.

[0379] In some cases, the design and / or manufacture of the device may not require various arrangements or staging of treatment phases. Figure 3 As shown by the dotted lines in , the design and / or manufacture of orthodontic appliances and possible specific orthodontic treatments may include using a representation of a patient's teeth (e.g., receiving a digital representation 310 of the patient's teeth) and then designing and / or manufacturing the orthodontic appliance based on the representation of the patient's teeth in the arrangement represented by the received representation.

[0380] G. Treatment by pathway

[0381] In some embodiments, the present disclosure provides a method of repositioning a patient's teeth, the method comprising applying an orthodontic appliance disclosed herein to at least one of the patient's teeth, and moving at least one of the patient's teeth toward an intermediate or final tooth arrangement.

[0382] In some embodiments, the present disclosure provides a method of repositioning a patient's teeth, the method comprising:

[0383] generating a treatment plan for the patient, the plan including a plurality of intermediate tooth arrangements for moving the teeth along a treatment path from an initial arrangement to a final arrangement;

[0384] producing a 3D printed orthodontic device comprising a plurality of weakly cross-linked units comprising weak cross-links; and

[0385] The orthodontic appliance is used to move at least one tooth of the patient along a path toward an intermediate or final tooth arrangement. In a preferred embodiment, the weak crosslink has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol. In some embodiments, the weak crosslink unit is a weak crosslink.

[0386] refer to Figure 4 , a method 400 according to the present invention is shown. Various aspects of the method will be discussed in further detail below. The method includes receiving information about a patient's orthodontic condition and / or treatment information (402), generating an assessment of a case (404), and generating a treatment plan (406) for repositioning the patient's teeth. Briefly, the patient / treatment information will include obtaining data containing an initial arrangement of the patient's teeth, which typically includes obtaining an impression or scan of the patient's teeth prior to commencing treatment, and may also include identification of one or more treatment goals selected by the practitioner and / or patient. A case assessment (404) can be generated to assess the complexity or difficulty of moving specific patient teeth generally or specifically corresponding to the identified treatment goals, and may also include the practitioner's experience and / or comfort in implementing the desired orthodontic treatment. However, in some cases, the assessment may include simply identifying specific treatment options (e.g., appointment scheduling, progress tracking, etc.) that the patient and / or practitioner is interested in. This information and / or corresponding treatment plan will include identification of a desired final or target arrangement of the patient's teeth, and a plurality of planned successive or intermediate tooth arrangements for moving the teeth from the initial arrangement toward the selected final or target arrangement along a treatment path.

[0387] The method also includes generating customized treatment guidelines (408). A treatment plan typically includes multiple treatment phases, wherein the customized set of generated treatment guidelines corresponds to the phases of the treatment plan. The guidelines will include detailed information about the time and / or content (e.g., specific tasks) to be completed in a given treatment phase and will be sufficiently detailed to guide practitioners during the treatment phase, including less experienced practitioners or practitioners who are relatively new to a particular orthodontic treatment process. Because the guides are designed to correspond specifically to the treatment plan and provide guidance on activities specifically identified in the treatment information and / or generated treatment plan, the guides are said to be customized. The customized treatment guidelines are then provided to the practitioners to help guide them on how to provide treatment for a given phase. As described above, instruments can be generated based on the planned arrangement and provided to the practitioners and ultimately administered to the patient (410). Instruments are typically provided and / or administered in sets or batches of instruments, such as 2, 3, 4, 5, 6, 7, 8, 9 or more instruments, but are not limited to any particular administration scheme. Instruments can be provided to the practitioners simultaneously with a given set of guidelines, or the instruments and guidelines can be provided separately.

[0388] After treatment has begun according to the plan, and after appliances have been administered to the patient, treatment progress tracking is performed, such as by tooth matching, to assess the current and actual alignment of the patient's teeth and compare them to the planned alignment (412). If it is determined that the patient's teeth are on track and are being treated according to the treatment plan, then treatment will progress as planned and the treatment will proceed to the next treatment phase (414). If the patient's teeth have substantially achieved the final alignment originally planned, then treatment will proceed to the final treatment phase (414). If it is determined that the patient's teeth are tracking according to the treatment plan, but have not yet achieved the final alignment, the next set of appliances may be administered to the patient.

[0389] Table 1 below gives the threshold differences between the planned and actual positions of teeth, which are selected to indicate that the patient's teeth have progressed on path. If the patient's teeth have progressed at or within the threshold, the progress is considered on path. If the patient's teeth have progressed beyond the threshold, the progress is considered off path.

[0390]

[0391]

[0392] Table 1

[0393] The patient's teeth are determined to be on-path by comparing the teeth in their current positions to the teeth in their expected or planned positions and confirming that the teeth are within the parameter variances disclosed in Table 1. If the patient's teeth are determined to be on-path, then treatment can proceed according to the existing or original treatment plan. For example, one or more subsequent appliances, such as a next set of braces, can be administered to the patient determined to be on-path according to the treatment plan. Treatment can progress to a final stage and / or to a point in the treatment plan at which the bite match is repeated to determine whether the patient's teeth are on-path or if the teeth are off-path.

[0394] In some embodiments, as further disclosed herein, the present disclosure provides a method of treating a patient using a 3D-printed orthodontic appliance. In certain embodiments, a method of repositioning a patient's teeth (or in some embodiments, a single tooth) comprises: generating a treatment plan for the patient, the plan comprising a tooth arrangement for moving the teeth from an initial arrangement to a final arrangement along a treatment path; producing a 3D-printed orthodontic appliance; and using the orthodontic appliance to move at least one of the patient's teeth along the path toward an intermediate arrangement or a final tooth arrangement. In some embodiments, the 3D-printed orthodontic appliance is produced using a printable resin as further disclosed herein. The path performance can be determined, for example, from Table 1 above.

[0395] In some embodiments, the method further comprises tracking the progress of the patient's teeth along the treatment path after applying the orthodontic appliance. In certain embodiments, tracking comprises comparing the current arrangement of the patient's teeth with the planned arrangement of the teeth. As a non-limiting example, after the orthodontic appliance is first applied, over a period of time (e.g., two weeks), the current arrangement of the patient's teeth (i.e., when treating for two weeks) can be compared with the arrangement of the teeth in the treatment plan. In some embodiments, progress can also be tracked by comparing the current arrangement of the patient's teeth with the initial arrangement of the patient's teeth. For example, the time period can be greater than 3 days, greater than 4 days, greater than 5 days, greater than 6 days, greater than 7 days, greater than 8 days, greater than 9 days, greater than 10 days, greater than 11 days, greater than 12 days, greater than 13 days, greater than 2 weeks, greater than 3 weeks, greater than 4 weeks, or greater than 2 months. In some embodiments, the time period can be from at least 3 days to at most 4 weeks, from at least 3 days to at most 3 weeks, from at least 3 days to at most 2 weeks, from at least 4 days to at most 4 weeks, from at least 4 days to at most 3 weeks, or from at least 4 days to at most 2 weeks. In certain embodiments, the time period may restart after a new orthodontic appliance is administered.

[0396] In some embodiments, after a period of time of use of an orthodontic appliance as further disclosed herein, greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, greater than 90%, greater than 91%, greater than 92%, greater than 93%, greater than 94%, greater than 95%, greater than 96%, greater than 97%, greater than 98%, or greater than 99% of a patient's teeth comply with the treatment plan. In some embodiments, the period of time is 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 2 weeks, 3 weeks, 4 weeks, or greater than 4 weeks.

[0397] H. Performance after use

[0398] In some embodiments of the methods disclosed above, the 3D printed orthodontic appliance has a retained repositioning force (i.e., the repositioning force after the orthodontic appliance has been applied to or worn by a patient fo...

Claims

1. A composition comprising: A polymer chain comprising: a ring containing three or more ring members; a first bond in the ring that is between two ring members of a first group of three or more ring members and that has a bond dissociation energy less than or equal to 325 kJ / mol; as well as A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

2. A composition comprising: A polymer chain comprising: a ring comprising three or more ring members; a first bond in the ring between two ring members of a first group of three or more ring members, wherein upon activation of the catalyst, the first bond is convertible into a bond having a bond dissociation energy less than or equal to 325 kJ / mol; and A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

3. The composition of any one of claims 1-2, wherein the first bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol.

4. The composition of any one of claims 1-2, wherein the ring comprises a plurality of bonds between two sets of ring members, the bond dissociation energy of each of the plurality of bonds being at least 20 kJ / mol higher than the bond dissociation energy of the first bond.

5. The composition of any one of claims 1-2, wherein the ring comprises a substituted or unsubstituted cycloalkane or a derivative thereof, a substituted or unsubstituted heterocycle or a derivative thereof, or a substituted or unsubstituted inorganic ring or a derivative thereof.

6. The composition of any one of claims 1-2, wherein the first bond is a covalent bond, a plurality of hydrogen bonds, or an ionic bridge.

7. The composition of any one of claims 1-2, wherein the ring comprises a weak bridge comprising the first bond.

8. The composition of any one of claims 1-2, wherein the polymer chain comprises a first portion and a second portion, the first portion of the polymer chain being attached to the ring via a first linker, and the second portion of the polymer chain being attached to the ring via a second linker.

9. The composition of claim 8, wherein the ring is located between the first linker and the second linker, such that the first bond is located between the first linker and the second linker, and wherein the second bond is located between the first linker and the second linker.

10. The composition according to any one of claims 1-2, wherein the bond dissociation energy of the first bond is less than or equal to 300 kJ / mol.

11. The composition of claim 8, wherein the first and second portions of the polymer chain independently comprise a backbone, wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol higher than the bond dissociation energy of the first bond.

12. The composition of any one of claims 1-2, wherein the polymer chain comprises a plurality of rings, each of the plurality of rings comprising: three or more ring members; a first bond in the ring that is between two ring members of a first group of three or more ring members and that has a bond dissociation energy less than or equal to 325 kJ / mol; as well as A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

13. The composition of any one of claims 1-2, wherein the polymer chain comprises 0.1 wt% to 50 wt% of the rings.

14. The composition of any one of claims 1-2, wherein the polymer chain comprises a ratio of the total number of bonds of the ring to the total number of bonds of the polymer chain, and the ratio is from 1:2500 to 1:

10.

15. The composition of any one of claims 1-2, wherein the ring comprises 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more than 20 ring members.

16. The composition of any one of claims 1-2, wherein the ring comprises greater than 10 ring members.

17. The composition of any one of claims 1-2, wherein the first bond is a dynamic covalent bond.

18. The composition of any one of claims 1-2, wherein the first bond is a sulfur-sulfur bond, an oxygen-oxygen bond, a nitrogen-nitrogen bond, a silicon-sulfur bond, a silicon-silicon bond, a phosphorus-phosphorus bond, an oxygen-sulfur bond, a nitrogen-phosphorus bond, a carbon-phosphorus bond, a phosphorus-silicon bond, a carbon-sulfur bond, or a nitrogen-oxygen bond.

19. The composition of any one of claims 1-2, wherein the first bond is a non-polar covalent bond or a polar covalent bond.

20. The composition of any one of claims 1-2, wherein the bond dissociation energy of the first bond is measured as a bond dissociation energy or a bond breaking energy.

21. The composition of any one of claims 1-2, wherein the polymer chains are hydrophobic.

22. The composition of any one of claims 1-2, wherein the first bond has a strength less than 85% of the average carbon-carbon bond in polyethylene.

23. A polymeric material comprising the composition of any one of claims 1-22.

24. A polymer material comprising: a polymer chain comprising a ring including three or more ring members; a first bond in the ring that is between two ring members of a first group of three or more ring members and that has a bond dissociation energy less than or equal to 325 kJ / mol; as well as A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

25. A polymer material comprising: a polymer chain comprising a ring including three or more ring members and an activatable unit; an activatable unit in the ring between two ring members of a first group of three or more ring members, wherein upon activation of the catalyst, the activatable unit is convertible into a first bond having a bond dissociation energy less than or equal to 325 kJ / mol; and A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

26. The polymeric material of claim 25, further comprising the catalyst.

27. The polymeric material of any one of claims 24-25, wherein the polymeric material comprises less than 10 wt% hydrogen bonding units.

28. The polymeric material of any one of claims 24-25, wherein the polymeric material comprises less than 10 wt% water after being placed in an aqueous environment at 37°C for 24 hours.

29. The polymeric material of any one of claims 24-25, wherein the polymeric material is hydrophobic.

30. The polymeric material of claim 24, wherein the polymeric material comprises a plurality of rings, each of the rings comprising: three or more ring members; a first bond in the ring that is between two ring members of a first group of three or more ring members and that has a bond dissociation energy less than or equal to 325 kJ / mol; as well as A second bond in the ring is located between two ring members of a second group of three or more ring members and has a bond dissociation energy greater than 325 kJ / mol.

31. The polymeric material of any one of claims 24-25, wherein the polymeric material comprises greater than 0.1 wt% of the one or more rings.

32. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by one or more of the following: After being placed in an aqueous environment at 37°C for 24 hours, the tensile modulus is greater than or equal to 100 MPa; After being placed in an aqueous environment at 37°C for 24 hours, the yield tensile strength is greater than or equal to 5 MPa; After being placed in an aqueous environment at 37°C for 24 hours, the storage modulus is greater than or equal to 300 MPa; After being placed in an aqueous environment at 37°C for 24 hours, the residual bending stress after 24 hours is greater than or equal to 1.5 MPa; A hardness of 60 Shore A to 85 Shore D after 24 hours at 37°C in an aqueous environment; and After being placed in an aqueous environment at 37°C for 24 hours, the elongation at break is greater than or equal to 15%.

33. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by a residual bending stress greater than 5% when tested in a humid environment at 37°C for 24 hours.

34. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by a residual stress of 5% to 45% of the initial load after testing in a humid environment at 37°C for 24 hours.

35. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by a tensile modulus of 100 MPa to 3000 MPa after testing in a humid environment at 37°C for 24 hours.

36. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by an elongation at break greater than 10% after testing in a humid environment at 37°C for 24 hours.

37. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by a storage modulus of 0.1 MPa to 4000 MPa after testing in a humid environment at 37°C for 24 hours.

38. The polymeric material of any one of claims 24-25, wherein the polymeric material is characterized by a residual stress of 0.01 MPa to 15 MPa after testing in a humid environment at 37°C for 24 hours.

39. The polymeric material of any one of claims 24-25, wherein greater than 70% of visible light passes through the polymeric material.

40. The polymeric material of any one of claims 24-25, wherein the polymeric material is biocompatible, bioinert, or a combination thereof.

41. An orthodontic appliance comprising the polymeric material of any one of claims 23-40.

42. An orthodontic appliance comprising the composition of any one of claims 1-22.

43. The orthodontic appliance according to any one of claims 41-42, wherein the orthodontic appliance is an aligner, an expander or a spacer.

44. The orthodontic appliance of any one of claims 41-42, wherein the orthodontic appliance comprises a plurality of tooth-receiving cavities configured to reposition teeth from a first configuration toward a second configuration.

45. The orthodontic appliance of any one of claims 41-42, wherein the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition the teeth from an initial configuration toward a target configuration.

46. The orthodontic appliance of any one of claims 41-42, wherein the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition the teeth from an initial configuration to a target configuration according to a treatment plan.

47. The orthodontic appliance of any one of claims 41-42, wherein the orthodontic appliance is an aligner.

48. A resin comprising: a plurality of monomers, optionally wherein the plurality of monomers is contained in an oligomer having an average chain length of 1 kDa to 30 kDa; and Cyclic monomers comprising: A ring comprising: three or more ring members; a first bond between two ring members of a first group of three or more ring members and having a bond dissociation energy less than or equal to 325 kJ / mol; and a second bond between two ring members of a second group of three or more ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and A second linker is attached to the ring comprising a second reactive group.

49. A resin comprising: a plurality of monomers, optionally wherein the plurality of monomers is contained in an oligomer having an average chain length of 1 kDa to 30 kDa; A cyclic monomer comprising: A ring comprising: three or more ring members; an activatable unit positioned between two ring members of a first group of three or more ring members, wherein upon activation of the catalyst, the activatable unit is convertible into a first bond having a bond dissociation energy less than or equal to 325 kJ / mol; and a second bond between two ring members of a second group of three or more ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and A second linker is attached to the ring comprising a second reactive group.

50. The resin of claim 49 further comprising the catalyst.

51. The resin of any one of claims 48-49, further comprising an initiator.

52. The resin of any one of claims 48-49, wherein the first linker and the second linker are each covalently attached to the ring.

53. The resin of any one of claims 48-49, wherein the first linker and the second linker are each located outside of the ring.

54. The resin of claim 51, wherein the initiator is a photoinitiator, a thermal initiator, or a combination thereof.

55. The resin of any one of claims 48-49, wherein the first reactive group and the second reactive group each independently comprise an acrylate or derivative thereof, a methacrylate or derivative thereof, a thiol or derivative thereof, an epoxide or derivative thereof, an allyl ether or derivative thereof, a hydroxyl or derivative thereof, or an amine or derivative thereof.

56. The resin of any one of claims 48-49, wherein the bond dissociation energy of the first bond is less than or equal to 300 kJ / mol.

57. The resin of any one of claims 48-49, wherein the oligomer comprises a backbone, wherein the bond dissociation energy of all covalent bonds in the backbone is at least 20 kJ / mol higher than the bond dissociation energy of the first bond.

58. The resin of any one of claims 48-49, wherein the ring comprises a plurality of bonds between two sets of ring members, each of the plurality of bonds having a bond dissociation energy at least 20 kJ / mol greater than the bond dissociation energy of the first bond.

59. The resin of any one of claims 48-49, wherein the first bond is selected from the group consisting of a sulfur-sulfur bond, an oxygen-oxygen bond, a nitrogen-nitrogen bond, a silicon-sulfur bond, a silicon-silicon bond, a phosphorus-phosphorus bond, an oxygen-sulfur bond, a nitrogen-phosphorus bond, a carbon-phosphorus bond, a phosphorus-silicon bond, a carbon-sulfur bond, and a nitrogen-oxygen bond.

60. The resin of any one of claims 48-49, wherein the first bond is a non-polar covalent bond or a polar covalent bond.

61. The resin of any one of claims 48-49 comprising less than 10 wt% hydrogen bonding units.

62. The resin of any one of claims 48-49, further comprising a reactive diluent, a crosslinking modifier, a light blocker, a solvent, a glass transition temperature modifier, a thermal initiator, or a combination thereof.

63. The resin of any one of claims 48-49, further comprising at least one of a polymerization catalyst, an inhibitor, a plasticizer, a surface energy modifier, a pigment, a dye, a filler, a seed crystal, a crystallization catalyst, a bioagent, a catalyst for selective bond breaking, or any combination thereof.

64. The resin of any one of claims 48-49, wherein the oligomer comprises a polymerizable group.

65. The resin of claim 64, wherein the polymerizable group of the oligomer is selected from vinyl or derivatives thereof, allyl or derivatives thereof, allyl ether or derivatives thereof, acrylate or derivatives thereof, methacrylate or derivatives thereof, acrylamide or derivatives thereof, epoxy or derivatives thereof, oxetane or derivatives thereof, thiol or derivatives thereof, hydroxyl or derivatives thereof, or amine or derivatives thereof.

66. The resin of any one of claims 48-49, wherein the resin has a viscosity of 0.5 PaS to 20 PaS at a printable temperature.

67. The resin of claim 66, wherein the printable temperature is 70°C to 110°C.

68. The resin of claim 67, wherein the printable temperature is 90°C.

69. The resin of any one of claims 48-49, wherein the resin is capable of being 3D printed.

70. A method of forming a polymeric material, the method comprising: Providing the resin according to any one of claims 48 to 69; as well as The resin is cured using a light source to form the polymer material.

71. The method of claim 70, further comprising providing a catalyst for forming the first bond.

72. The method of claim 70, further comprising fabricating an object from the polymeric material.

73. The method of claim 72, wherein said manufacturing comprises printing using a 3D printer.

74. The method of claim 72, wherein the fabricating comprises thermal lithography.

75. The method of claim 72, wherein said manufacturing comprises digital light projection.

76. The method of claim 72, wherein the object is an orthodontic appliance.

77. The method of claim 76, wherein the orthodontic appliance is an aligner, an expander, or a spacer.

78. The method of claim 76, wherein the orthodontic appliance comprises a plurality of tooth-receiving cavities configured to reposition teeth from a first configuration toward a second configuration.

79. The method of claim 76, wherein the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition the teeth from an initial configuration toward a target configuration.

80. The method of claim 76, wherein the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition the teeth from an initial configuration to a target configuration according to a treatment plan.

81. The method of claim 76, wherein the object is an aligner.

82. A polymeric material produced by the method of any one of claims 70-81.

83. The polymeric material of claim 82, wherein stress applied to the polymeric material or composition breaks the first bond before breaking the second bond.

84. A method of repositioning a patient's teeth, the method comprising: applying an orthodontic appliance according to any one of claims 41 to 47 to at least one tooth of the patient; as well as At least one tooth of the patient is moved toward an intermediate or final dental arrangement.

85. A method of repositioning a patient's teeth, the method comprising: generating a treatment plan for the patient, the plan including a plurality of intermediate tooth arrangements for moving the teeth along a treatment path from an initial arrangement to a final arrangement; Production of 3D printed orthodontic devices, including: a ring containing three or more ring members; a first bond in the ring that is between two ring members of a first group of three or more ring members and that has a bond dissociation energy less than or equal to 325 kJ / mol; and a second bond in the ring that is between two ring members of a second group of three or more ring members and that has a bond dissociation energy greater than 325 kJ / mol; and At least one tooth of the patient is moved along a path toward an intermediate or final tooth arrangement using the orthodontic appliance.

86. A method of repositioning a patient's teeth, the method comprising: generating a treatment plan for the patient, the plan including a plurality of intermediate tooth arrangements for moving the teeth along a treatment path from an initial arrangement to a final arrangement; Producing an orthodontic device according to any one of claims 41 to 47; as well as moving at least one tooth of the patient along a path toward an intermediate or final tooth arrangement using the orthodontic appliance, wherein the first bond has a bond dissociation energy of 50 kJ / mol to 325 kJ / mol.

87. The method of claim 86, further comprising tracking the progress of the patient's teeth along the treatment path after applying the orthodontic appliance, the tracking comprising comparing the current arrangement of the patient's teeth with the planned arrangement of the teeth.

88. The method of any one of claims 86-87, wherein after 2 weeks of treatment, greater than 60% of the patient's teeth comply with the treatment plan.

89. The method of any one of claims 86-87, wherein the orthodontic appliance has a retained repositioning force on at least one tooth of the patient after 2 days of at least 10% of the repositioning force initially provided to the at least one tooth of the patient.

90. The method of any one of claims 86-87, further comprising effecting movement of at least one tooth of the patient along a path to the intermediate arrangement or the final tooth arrangement.

91. A composition comprising: Cyclic monomers comprising: A ring comprising: three or more ring members; a first bond between two ring members of a first group of three or more ring members and having a bond dissociation energy less than or equal to 325 kJ / mol; a second bond between two ring members of a second group of three or more ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and A second linker is attached to the ring comprising a second reactive group.

92. A composition comprising: Cyclic monomers comprising: A ring comprising: three or more ring members; an activatable unit positioned between two ring members of a first group of three or more ring members, wherein upon activation of the catalyst, the activatable unit is convertible into a first bond having a bond dissociation energy less than or equal to 325 kJ / mol; and a second bond between two ring members of a second group of three or more ring members and having a bond dissociation energy greater than 325 kJ / mol; a first linker attached to the ring comprising a first reactive group; and A second linker is attached to the ring comprising a second reactive group.

93. The composition of claim 92, further comprising the catalyst.

94. The composition of any one of claims 91-92, further comprising an initiator.

95. The composition of any one of claims 91-92, wherein the first linker and the second linker are each covalently attached to the ring.

96. The composition of any one of claims 91-92, wherein the first linker and the second linker are each located outside of the ring.

97. A composition according to any one of claims 91-92, wherein the first reactive group and the second reactive group each independently comprise an acrylate or derivative thereof, a methacrylate or derivative thereof, a thiol or derivative thereof, an epoxide or derivative thereof, an allyl ether or derivative thereof, a hydroxyl or derivative thereof, or an amine or derivative thereof.

98. The composition of any one of claims 91-92, wherein the bond dissociation energy of the first bond is less than or equal to 300 kJ / mol.

99. The composition of any one of claims 91-92, wherein the ring comprises a plurality of bonds between two sets of ring members, each of the plurality of bonds having a bond dissociation energy at least 20 kJ / mol greater than the bond dissociation energy of the first bond.

100. The composition of any one of claims 91-92, wherein the first bond is selected from the group consisting of a sulfur-sulfur bond, an oxygen-oxygen bond, a nitrogen-nitrogen bond, a silicon-sulfur bond, a silicon-silicon bond, a phosphorus-phosphorus bond, an oxygen-sulfur bond, a nitrogen-phosphorus bond, a carbon-phosphorus bond, a phosphorus-silicon bond, a carbon-sulfur bond, and a nitrogen-oxygen bond.

101. The composition of any one of claims 91-92, wherein the first bond is a non-polar covalent bond or a polar covalent bond.

102. The composition of any one of claims 91-92, comprising less than 10 wt% hydrogen bonding units.

103. The composition of any one of claims 91-92, wherein the composition is capable of being 3D printed.

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