Norbornene containing macromers, methods of making same, and uses thereof

Abstract

Macromers and compositions, methods of making macromers and making objects and articles of manufacture, and objects and articles of manufacture. In various examples, a macromer comprises oligomer group(s) comprising one or more norbornene group(s). In various examples, a method of making macromer(s) comprises reacting oligomer(s), norbornene group precursor(s), and optionally, base catalyst(s) and / or aliphatic epoxide(s) to form the macromer(s). In various examples, a composition (which may be an emulsion), comprises macromer(s); and optionally, crosslinker(s), photoadditive(s), thermal additive(s), diluent(s), or any combination thereof. In various examples, a method of forming an object or an article of manufacture comprises irradiating or thermally treating a monolith comprising one or more composition(s), where crosslinking groups are formed. In various examples, an object or an article of manufacture, comprises at least partially crosslinked macromer(s) and may be porous and / or may comprise an interpenetrating network.

Description

NORBORNENE CONTAINING MACROMERS, METHODS OF MAKING SAME, AND USES THEREOFCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Nos. 63 / 572,327, filed March 31, 2024 and entitled “Norbomene Containing Macromers, Methods of Making Same, and Uses Thereof,” and 63 / 688,127, filed August 28, 2024 and entitled “Norbornene Containing Macromers, Methods of Making Same, and Uses Thereof.” The entire contents of the above-identified priority applications are hereby fully incorporated herein by reference in their entirety.BACKGROUND

[0002] Except for mineralized tissues, most human organs are viscoelastic and have complex 3D geometry. An exciting method to build a complex 3D object is Digital Light Processing (DLP). The 3D printing technique uses projected ultraviolet (UV) patterns to cure photopolymers layer by layer, balancing speed, resolution, and cost. Nevertheless, DLP- printable photopolymers with good biocompatibility that are elastic, degradable, and affordable are rare.

[0003] Thiol -norbornene photopolymers are excellent for vat photopolymerization due to their facile click chemistry. Nevertheless, their 3D-printing is mainly limited to hydrogels that comprise norbornene-functionalized gelatin, hyaluronic acid, methylcellulose, and chitosan. An exception is 4Degra™, a 3D-printable photopolymer that comprises polycarbonate with pendant norbornenes. Nevertheless, thiol -norbornene photopolymers are difficult to scale because their synthesis uses toxic coupling agents, laborious purification, and, in some cases, moisture-sensitive catalysts. While thiol cross-linkers are commodity chemicals, a common norbornene-functionalized macromer — such as norbornene- functionalized polyethylene glycol — currently costs about $315 for 1 g. This is more expensive than a 12K resolution Digital Light Processing (DLP) printer (ANY CUBIC Photon Mono M5s, currently $269). Because most DLP printers need at least 30 mL of photopolymer to coat the bottom of the resin vat, available norbornene-functionalized macromers are too cost-prohibitive to 3D print at scale.SUMMARY OF THE DISCLOSURE

[0004] The present disclosure provides, inter alia, macromers and compositions, and methods of making macromers. The present disclosure also provides uses of macromers and compositions.

[0005] In various examples, the present disclosure provides macromers. In various examples, the macromer comprises one or more oligomer group(s), each oligomer group comprising one or more norbomene group(s). In various examples, the oligomer group(s) comprise the following structure: OG-(NBG)x, where OG is an oligomer group, NBG is a norbomene group, and x is 1 to 20, including all integer numbers of norbornene groups and ranges therebetween). In various examples, each of the oligomer group(s) independently comprises a plurality repeat groups independently chosen from ether repeat units, dimethylsilioxane repeat units, structural analogs thereof, and any combination thereof. In various examples, the oligomer group(s) independently comprise: one or more polyhydroxyalkanoate(s), one or more poly caprolactone diol group(s), polylactide group(s), polyglycolide group(s), one or more polyether group(s), one or more polypropylene glycol group(s), one or more polyethylene group(s), one or more polytetrahydrofuran group(s), one or more polycarbonate group(s), one or more polycarbonate diol group(s), one or more polycarbonate triol group(s), one or more PDMS bisamine group(s), or a structural analog thereof, or the like, or any combination thereof. In various examples, the norbornene group(s) independently comprise the following structure:structural analog thereof, a stereoisomer thereof, an isotopic variant, or the like thereof, where L is a linking group or where two L groups taken together form a ring. In various examples, the oligomer group(s) independently comprise(s) a molecular weight of about 200 g / mol to about 10,000 g / mol, including all 0.1 g / mol values and ranges therebetween.

[0006] In various examples, the present disclosure provides compositions. In various examples, a composition comprises one or more macromer(s) of the present disclosure. In various examples, the macromer(s) is / are present at about 50 to about 99 wt.% (relative to the total weight of the composition) , including all 0.1 wt.% values and ranges therebetween. In various examples, the composition further comprises one or more crosslinker(s); one or more photoadditive(s), wherein at least one of the photoadditive(s) is / are one or morephotoinitiator(s) and / or one or more thermal additive(s), wherein at least one of the thermal additives is a thermal initiator; and optionally, one or more diluent(s) and / or one or more solvent(s). In various examples, the crosslinker(s) is / are chosen from thiols, dithiolanes, structural analogs thereof, and the like, and any combination thereof. In various examples, the crosslinker(s) is / are present at about 5 to about 20 wt.% (e.g., relative to the total weight the composition), including all O.wt.% values and ranges therebetween. In various examples, the photoadditive(s) is / are chosen from photoinitiator(s), photo absorber(s), stabilizer(s), and the like, and any combination thereof) and / or the thermal additive(s) is / are chosen from thermal initiator(s), thermal absorber(s), stabilizer(s), and the like, and any combination thereof. In various examples, the photoadditive(s) and / or thermal additive(s) is / are present at about 0.01 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s) or the total weight of the composition), including all 0.1 wt.% values and ranges therebetween. In various examples, the diluent(s) is / are reactive diluent(s) chosen from divinyl triethylene glycol, trimethylolpropane diallyl ether, limonene, propargyl alcohol, structural analogs thereof, and the like, and any combination thereof and / or diluent(s) chosen from propylene carbonate, ethylene glycol, dimethyl sulfoxide, ethyl acetate, acetone, structural analogs thereof, and the like, and any combination thereof. In various examples, the diluent(s) is / are present at about 1 to about 20 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween. In various examples, the composition is an emulsion or the like. In various examples, the composition further comprises water and optionally, one or more solvent(s) chosen from hydrocarbons (such as, for example, hexane, octane, structural analogs thereof, and the like, and any combination thereof), ketones (such as, for example, acetone, structural analogs thereof, and the like, and any combination thereof), alkyl benzenes (such as, for example, toluene, xylene, structural analogs thereof, and the like, and any combination thereof), halogenated analogs thereof, structural analogs thereof, halogenated solvents, and the like, and any combination thereof, and any combination thereof, and one or more thickener(s) and / or one or more emulsifier(s).

[0007] In various examples, the present disclosure provides a method of making macromers. In various examples, a method of making a macromer or macromers (such as, for example, macromer(s) of the present disclosure) comprises: forming a reaction mixture comprising; one or more oligomer(s), one or more norbornene group precursor(s), and, optionally, one or more base catalyst(s) and / or one or more aliphatic epoxide(s); and holding the reaction mixture, where the macromer(s) is / are formed. In various examples, the norbomene group precursor(s) is / are chosen from carbic anhydride (CPMA), norbornylhalides (such as, for example, norbornyl fluoride, norbornyl chloride, norbomyl bromide, norbomyl iodide, a structural analog thereof, or the like, or a combination thereof), structural analogs thereof, and the like, and any combination thereof. In various examples, the oligomer(s) independently comprise a plurality of ether repeat units, a plurality of dimethylsilioxane repeat units, or a structural analog thereof, or any combination thereof.

[0008] In various examples, the present disclosure provides uses of macromers and compositions of the present disclosure. In various examples, a method of forming an object or an article of manufacture comprises irradiating with electromagnetic radiation at least a portion or all of a monolith or thermally treating a monolith comprising one or more composition(s) of the present disclosure, where a plurality of crosslinking groups is formed in the at least a portion or all of the at least a portion or all of the irradiated monolith or thermally treated monolith comprising the one or more composition(s) and the object or the article of manufacture is formed. In various examples, about 10% to about 100% of the norbomenyl groups of the macromer(s) of the one or more composition(s), including all 0.1 percent values and ranges therebetween, is photoreacted or thermally reacted to form the plurality of crosslinking groups. In various examples, the monolith is a film, an object (which may be a three-dimensional object), or the like and the method further comprises forming the film, the object (which may be a three-dimensional object), or the like comprising the composition(s). In various examples, the film, the object (which may be a three-dimensional object), or the like is formed prior to and / or during the irradiating with electromagnetic radiation of or thermally treating the composition(s). In various examples, the method is an additive manufacturing method or the like. In various examples, the additive manufacturing method is a 3-D printing method or the like. In various examples, the 3-D printing method is digital light processing (DLP), stereolithography (SLA), volumetric printing, UV inkjet printing, or two-photon polymerization printing, or the like. In various examples, the method of forming an object or an article of manufacture, or the like, further comprises functionalizing the object or the article of manufacture. In various examples, the method of forming an object or an article of manufacture, or the like, further comprises one or more post-irradiation or post- thermal treatment process(es) chosen from (i) in the case of an object or an article of manufacture formed by irradiation, irradiating or thermally-treating the object or the article of manufacture formed by the irradiation; (ii) in the case of an object or an article of manufacture formed by thermal treatment, irradiating or thermally-treating the object or the article of manufacture formed by the irradiation.

[0009] In various examples, an object or an article of manufacture or the like comprises one or more at least partially, substantially, or completely crosslinked macromer(s) of the present disclosure. In various examples, the object is a vascular graft (such as, for example, an aortic arch or the like) or the like, which may be porous. In various examples, the article of manufacture or the like is a porous scaffold, at least a part or portion of a surgical prosthesis, at least a part or portion of a wearable electronic object or device, at least a part or portion of an earbud insert, at least a part or portion of a microfluidic device, or the like. In various examples, the object or the article of manufacture or the like is at least partially or is porous. In various examples, the object or the article of manufacture or the like comprises an interpenetrating network comprising a first network comprising the one or more at least partially, substantially, or completely crosslinked macromer(s) of the present disclosure and a second network comprising one or more at least partially, substantially, or completely crosslinked polymer(s), where the first network and the second network are interpenetrating networks.

[0010] In various examples, thiol -norb omene resins are synthesized either with alcoholysis catalyzed by a green catalyst, such as, for example, caffeine or the like, or aminolysis that does not use a catalyst and produces water as the only byproduct. These two green reactions are readily scaled up to 100 g scale or greater. The resultant resins can be printed neat or as an emulsion. Both methods produce elastomers, with the emulsion affording a porous structure useful for various applications. As an option, in various examples, a secondary, interpenetrating network of polymers, such as, for example, poly(acrylate)s or the like, is integrated with the crosslinked thiol -norb omene resins, for example, to increase their toughness, making the final product easy to handle and robust.BRIEF DESCRIPTION OF THE FIGURES[OOH] For a fuller understanding of the nature and objects of the disclosure, reference should be made to the following detailed description taken in conjunction with the accompanying figures.

[0012] FIG. 1 shows (A)1H-NMR spectra of norbomene dicarboximide-functionalized polymers showing their end group structure (500 MHz, CDCh). Full spectra are shown in FIG. 4 and 5. (B) An example of macromers and products of the present disclosure.

[0013] FIG. 2 shows photorheology and viscosity of representative photopolymers (names are abbreviated to their respective backbone; see Table 1). The photorheology data of 2kPPG and 7kPDMS are in FIG. 4. Ultraviolet (UV) radiation (400-500 nm, 10 mW / cm2) isswitched on at 10 s (s = second(s)) (G’: storage modulus; G” loss modulus). The cross-linker is either polySH or PETMP, and all formulations use the same photo-additives. Diphenyl (2,4,6-trimethylbenzoyl)-phosphine oxide (TPO) initiates UV cross-linking; 2, 2,6,6- tetramethylpiperidine 1-oxyl (TEMPO) scavenges radicals to increase resin shelf life and resolution; and 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene (BBOT) absorbs UV to reduce UV penetration depth.

[0014] FIG. 3 shows (A) Representative stress-strain curves of 3D printed thiol- norbomene networks (photopolymers’ names are abbreviated to their polymer backbone due to space constrains). (B) Photograph and scanning electron microscopy (SEM) image (scale bar: 500 pm) of a porous gyroid puck and a porous gyroid puck tube; pores are estimated to be 200-300 pm in diameter. (C,D) High-fidelity DLP 3D-printing of true-to-scale aortic arch rendered from patient Computed Tomography (CT) scans. (E) Surface functionalization with cysteamine. The ruler division is 1 mm.

[0015] FIG. 4 shows 'H NMR (CDC13, 500 MHz) of 0.9kPDMS-2CA.

[0016] FIG. 5 shows 'H NMR (CDCI3, 500 MHz) of 2kPPG-2CA.

[0017] FIG. 6 shows photoreheology of 7kPDMS-5CA:polySH and 2kPPG-2CA:PETMP (left), and 5kPPG-3CA:PETMP (right); UV (400-500 nm, 10 mW / cm2) was switched on at 10 s.

[0018] FIG. 7 shows diffusion NMR (CDCI3, 500 MHz) of 5kPPG-3CA.

[0019] FIG. 8 shows bottom view of aorta (~0.6 mm wall thickness) printed from7kPDMS-5CA:polySH showing patent branches and flexible structure.

[0020] FIG. 9 shows photograph of aorta model (2 mm wall thickness) printed from 5kPDMS-2CA:polySH.

[0021] FIG. 10 shows FT-IR (x axis: wavenumber (cm ), y axis: Absorbance) of various specimens (OSTE: off stoichiometric photopolymer comprising 0.9kPDMS-2CA and 0.7 eq of PETMP) showing C=C stretch of norbomene (labeled with *) overlaps with carbonyl C=O stretch of PETMP.

[0022] FIG. 11 shows ^H COSY of tPCL-CA-POlOO (500 MHz, CDC13) shows the structural variation of the CA-PO linkage and the lack of ether formation. Gel Permeation Chromatography (GPC) traces (tetrahydrofuran mobile phase at 30 °C, polystyrene standards) show tPCL-CA-PO 100’s unimodal distribution (Mn = 1.7 kDa, D = 1.39). 'H- NMR (500 MHz, CDCI3) of CA-functionalized bPCL shows uncatalyzed condensation (no PO, no caffeine) and CITRO (17 h or 44 h reaction time) controlling the chain-endfunctionality (the asterisk denotes unreacted CA. R: H or ring opened PO). The doublet at 1.3 ppm is from unreacted PO before its evaporation in vacuo.10023] FIG. 12 shows (A) The thiol cross-linker and photo-additives used in photopolymers. A stoichiometric amount of or less PETMP adjusts the mechanical properties of the photopolymers. TPO initiates the radical reaction under UV; BBOT absorbs UV to reduce penetration depth; and TEMPO is a radical scavenger. (B) The general structure of the photopolymers using PCL-CA-POIOO as an example.

[0024] FIG. 13 shows representative 3D-printed products. (A) A photograph (1 mm ruler division) and a scanning electron microscopy (SEM) image (scale bar: 500 pm) of porous gyroid pucks. (B) Artery STL models rendered from anonymized patient DICOM scans and resultant 3D-printed models from a DLP printer. The photopolymer is bPCL-CA-POlOO, which is representative of the printability of other photopolymers in Table 2.

[0025] FIG. 14 shows (A-D) cyclic tensile testing of dog-bone shaped specimens 3D printed from various photopolymers as noted in the plot.

[0026] FIG. 15 shows uniaxial ring test of aortic arch 3D printed from 0.7-bPCL-CA (abbreviated as 0.7-bPCL in the figure) or Formlabs Biomed Elastic 50A. The ring is taken from the ascending aorta portion.

[0027] FIG. 16 shows (A) Degradation profiles of tPCL-CA-POlOO, tPCL-CA-PO41, and bPCL-CA-POlOO networks (n = 3 each), with SEM images showing the surface of dogbone shaped specimens of tPCL-CA-POlOO before (top) and after (bottom) 48 h of immersion in 0.25 M NaOH at 37 °C (scale bar: 250 pm). (B) Mechanical properties of fresh and partially degraded tPCL-CA-POlOO network (n = 3, *p<0.05, **p<0.01, ***p<0.001). (C) Mechanical properties of fresh and partially degraded tPCL-CA-PO41 network (n = 3, ns: not significant). Statistical significance is determined via Student’s t-test by comparing degraded samples with fresh samples.

[0028] FIG. 17 shows (A) human umbilical vein endothelial cells (HUVECs) viability (n = 3, >75%) on the bPCL-CA network and tPCL-CA-POlOO network. An ATP -based luminescent cell viability assay is used. Viability is obtained by HUVEC luminescence signal on the test surface normalized by tissue-culture-treated polystyrene (TCPS). HUVECs viability displays no statistical significance (ns) between bPCL-CA and tPCL-CA-POlOO (statistical significance is determined via Student’s t-test). (B) Calcein-AM staining of HUVECs on Day 4 of the in vitro test (scale bar: 100 pm). (C) Subcutaneous tPCL-CA- PO100 implants explanted from mice after 15 days; hematoxylin and eosin (H&E) stainingshows little inflammatory response and healthy surrounding tissues. The implant is marked with Cell infiltration in the pores is outlined using a box (scale bar: 100 pm).

[0029] FIG. 18 shows 'H-NMR (CDCh, 500 MHz) of bPCL-CA. * is from the methylene proton of unreacted CA monomer.

[0030] FIG. 19 shows diffusion NMR (CDCh, 500 MHz) of tPCL-CA-POlOO.

[0031] FIG. 20 shows Gel Permeation Chromatography (GPC) trace of tPCL-CA-PO41.

[0032] FIG. 21 shows 'H-NMR of bPCL-CA-POlOO. e’ and f are from PO ring-opened at the tertiary carbon.

[0033] FIG. 22 shows 'H-NMR of tPCL-CA-POlOO. e’ and f are from PO ring-opened at the tertiary carbon.

[0034] FIG. 23 shows 3D printed microfluidic devices. (Left) cork-screw-shaped channels with progressively smaller diameter (bottom to top: 1mm, 500 pm, 250 pm). (Right) A simple “2D” mixing device (the widest channel is 1 mm in diameter. Open channels are visualized with food dye.

[0035] FIG. 24 shows bottom view and manipulation of DLP-printed aorta model.

[0036] FIG. 25 shows degradation of bPCL-CA network (n=3) in 60 mM NaOH at 37 °C.

[0037] FIG. 26 shows change of bPCL-CA-POlOO network’s mechanical properties over the course of degradation in 0.25 M NaOH at 37 °C (ns: not significant, * p<0.05). Statistical significance is determined via Student’s t-test by comparing degraded samples with fresh samples.

[0038] FIG. 27 shows calcein-AM staining of HUVECs on various samples (scale bar: 100 pm).

[0039] FIG. 28 shows growth curves of HUVECs on various samples. TCPS: tissue- culture-treated polystyrene.

[0040] FIG. 29 shows a Scanning Electron Microscopy (SEM) image of a DLP-printed PolyHIPE cross section.

[0041] FIG. 30 shows an SEM of DLP-printed PolyHIPE Surface.

[0042] FIG. 31 shows mechanical properties and porosity of PolyHIPE-IPN. (A) Comparison between tensile properties of polyHIPE and polyHIPE-IPN. (B) Uniaxial tensile testing of polyHIPE-IPN (n = 3). (C) Uniaxial tensile testing of autoclaved polyHIPE-IPN (triplicate repeat (n = 3)). (D) SEM image (scale bar: 200 pm) of the cross section of dogbone-shaped polyHIPE-IPN. All dogbone samples are soaked in water prior to mechanical testing.DETAILED DESCRIPTION OF THE DISCLOSURE

[0043] Although subject matter of the present disclosure is described in terms of certain examples, other examples, including examples that do not provide all of the benefits and features set forth herein, are also within the scope of this disclosure. For example, various structural, logical, and process step changes may be made without departing from the scope of the disclosure.

[0044] As used herein, unless otherwise indicated, “about”, “substantially”, or “the like”, when used in connection with a measurable variable (such as, for example, a parameter, an amount, a temporal duration, or the like) or a list of alternatives, is meant to encompass variations of and from the specified value including, but not limited to, those within experimental error (which can be determined by, e.g., a given data set, an art accepted standard, etc. and / or with, e.g., a given confidence interval (e.g., 90%, 95%, or more confidence interval from the mean), such as, for example, variations of + / - 10% or less, + / -5% or less, + / -1% or less, and + / -0.1% or less of and from the specified value), insofar such variations in a variable and / or variations in the alternatives are appropriate to perform in the instant disclosure. As used herein, the term “about” may mean that the amount or value in question is the exact value or a value that provides equivalent results or effects as recited in the claims or taught herein. That is, it is understood that amounts, sizes, compositions, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error, or the like, or other factors known to those of skill in the art such that equivalent results or effects are obtained. In general, an amount, size, composition, parameter, or other quantity or characteristic, or alternative is “about” or “the like,” whether or not expressly stated to be such. It is understood that where “about,” is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0045] Ranges of values are disclosed herein. The ranges set out a lower limit value and an upper limit value. Unless otherwise stated, the ranges include the lower limit value, the upper limit value, and all values between the lower limit value and the upper limit value, including, but not limited to, all values to the magnitude of the smallest value (either the lower limit value or the upper limit value) of a range. It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within thatrange as if each numerical value and sub-range is explicitly recited. To illustrate, a numerical range of “0.1% to 5%” should be interpreted to include not only the explicitly recited values of 0.1% to 5%, but also, unless otherwise stated, include individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.5% to 1.1%; 0.5% to 2.4%; 0.5% to 3.2%, and 0.5% to 4.4%, and other possible sub-ranges) within the indicated range. It is also understood (as presented above) that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms a further disclosure. For example, if the value “about 10” is disclosed, then “10” is also disclosed.

[0046] As used herein, unless otherwise stated, the term “group” refers to a chemical entity that is monovalent (i.e., has one terminus that can be (is) covalently bonded to other chemical species), divalent, or polyvalent (i.e., has two or more termini that can be (are) covalently bonded to other chemical species). The term “group” also includes radicals (e.g., monovalent radicals and multivalent radicals, such as, for example, divalent radicals, trivalent radicals, and the like). Illustrative examples of groups include:

[0047] As used herein, unless otherwise indicated, the term “alkyl group” refers to branched or unbranched saturated hydrocarbon groups. Examples of alkyl groups include, but are not limited to, methyl groups, ethyl groups, propyl groups, butyl groups, isopropyl groups, tert-butyl groups, and structural analogs thereof, and the like. For example, the alkyl group is Ci to C20, including all integer numbers of carbons and ranges of numbers of carbons therebetween (e.g., Ci, C2, C3, C4, C5, C6, C7, C8, C9, C10, Cn, C12, C13, C14, C15, Ci6, C17, Ci8, C19, and C20). The alkyl group may be unsubstituted or substituted with one or more substituents. Examples of substituents include, but are not limited to, halide groups (-F, -Cl, - Br, and -I), aryl groups, halogenated aryl groups, alkoxide groups, amine groups, nitro groups, carboxylate groups, carboxylic acids, ether groups, silyl ether groups, alcohol groups, alkyne groups (e.g., acetylenyl groups and the like), and structural analogs thereof, and the like, and any combination thereof.

[0048] As used herein, unless otherwise indicated, the term “aryl group” refers to C5 to C30 aromatic or partially aromatic carbocyclic groups, including all integer numbers of carbons and ranges of numbers of carbons therebetween (e.g., C5, Ce, C7, Cs, C9, C10, Cn, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24, C25, C26, C27, C28, C29, and C30). Aryl groups may be referred to as aromatic groups. Aryl groups may be polyaryl groups, such as, for example, fused rings, biaryl groups, and structural analogs thereof, and the like, and any combination thereof. Aryl groups may be unsubstituted or substituted with one or more substituents. Examples of substituents include, but are not limited to, halide groups (-F, -Cl, - Br, and -I), aliphatic groups (e.g., alkyl groups, alkenyl groups, alkynyl groups, and the like), aryl groups, alkoxides, carboxylates, carboxylic acids, ether groups, and the like, and combinations thereof. Examples of aryl groups include, but are not limited to, phenyl groups, biaryl groups (e.g., biphenyl groups and the like), fused ring groups (e.g., naphthyl groups and the like), hydroxybenzyl groups, tolyl groups, xylyl groups, furanyl groups, benzofuranyl groups, indolyl groups, imidazolyl groups, benzimidazolyl groups, pyridinyl groups, and structural analogs thereof, and the like.

[0049] As used herein, unless otherwise stated, the term “structural analog” refers to any reactant, reaction component, composition component or the like (e.g., macromer, norbomene group precursor, base catalyst, crosslinker, photoadditive, thermal additive, solvent, diluent, or the like), or any portion thereof (such as, for example, one or more group(s) thereof or the like) or group if one atom or group of atoms, functional group or functional groups, or substructure or substructures is / are replaced with another atom or group of atoms, functional group or functional groups, substructure or substructures, or the like. In various examples, the term “structural analog” refers to any group that is derived from an original reactant, reaction component, composition component or the like (e.g., macromer, norbomene group precursor, base catalyst, crosslinker, photoadditive, thermal additive, solvent, diluent, or the like), or the like or a portion thereof (such as, for example, one or more group(s) thereof or the like) or the like by a chemical reaction, where the reactant, reaction component, composition component or the like (e.g., macromer, norbornene group precursor, base catalyst, crosslinker, photoadditive, thermal additive, solvent, diluent, or the like) or the portion thereof (such as, for example, one or more group(s) thereof or the like) or the like is modified or partially substituted such that at least one structural feature of the reactant, reaction component, composition component or the like (e.g., macromer, norbomene group precursor, base catalyst, crosslinker, photoadditive, thermal additive,solvent, diluent, or the like) or the portion thereof (such as, for example, one or more group(s) thereof or the like) or the like is retained.10050] The present disclosure describes, inter alia, macromers and methods of making same. In various examples, the present disclosure also provides uses of the macromers.

[0051] In an aspect, the present disclosure provides macromers. In various examples, a macromer comprises one or more norbornene groups. Examples of macromers are shown in FIG. 1(B). In various examples, a macromer is produced by a method or used in a method of the present disclosure. Non-limiting examples of macromers are disclosed herein.

[0052] In various examples, a macromer (e.g., a functionalized macromer or norbomene- functionalized macromer) comprises one or more (e.g., two or more) norbornene groups (e.g., terminal norbornene groups, pendant norbornene groups, or the like, or any combination thereof). In various examples, an oligomer group is derived from any oligomer / polymer comprising one or more alcohol group(s), amine group(s), or any combination thereof, such as, for example, polyetheramines (such as, for example, Jeffamine®, or the like), polytetrahydrofuran, polypropylene glycol, polycarbonate diol, polycarbonate triol, or a structural analog thereof, or the like. In various examples, the alcohol group(s), amine group(s), or any combination thereof are independently a terminal group, a pendant group (e.g., disposed on a side chain of the macromer backbone, or the like). In various examples, macromer does not comprise a norbornene group in the backbone of the macromer.

[0053] In various examples, a macromer is a compound. In various examples, a macromer comprises one or more oligomer group(s), each oligomer group comprising one or more (e.g., two or more norbornene groups). In various examples, the norbomene group(s) is / are terminal norbomene group(s). In various examples, a macromer comprises one or more of the following structure: OG-(-NBG)x, where OG is an oligomer group and NBG is a norbomene group. In various examples, x is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, etc.

[0054] In various examples, an oligomer group comprises a plurality of ether (e.g., polyether or the like) repeat units, a plurality of dimethylsilioxane repeat units (e.g., polydimethylsiloxane or the like) repeat units, or the like, or any combination thereof. In various examples, an oligomer group is derived from any oligomer / polymer comprising one or more alcohol group(s), amine group(s), or any combination thereof, such as, for example, polyetheramines (such as, for example, Jeffamine®, or the like), polytetrahydrofuran, polypropylene glycol, polycarbonate diol, polycarbonate triol, or a structural analog thereof, or the like. In various examples, the alcohol group(s), amine group(s), or any combinationthereof are independently a terminal group, a pendant group (e.g., disposed on a side chain of the macromer backbone, or the like). In various examples, an oligomer group comprises a group or groups derived from small-molecule bifunctional / multi-functional alcohol / amines, including, but not limited to, 1,3 -propanediol, glycerol, 1,6-hexanediol, hexamethylenediamine, Jeffamine®, structural analogs thereof, and the like.

[0055] In various examples, each oligomer group of a macromer is formed from (or derived from) an oligomer group comprising a plurality of ether (e.g., polyether or the like) repeat units, dimethylsilioxane repeat units (e.g., polydimethyl siloxane or the like) repeat units, or a structural analog(s) thereof, or a combination thereof. In various examples, the oligomer group(s) of a macromer independently comprise(s) the following structure:(i) one or more polyhydroxyalkanoate(s); (ii) one or more PCL diol group(s) (or group(s) independently derived from a PCL diol oligomer) (e.g.,or a structural analog thereof (e.g., where n is independently 1 to 100, including all integer numbers and ranges therebetween) or a structural analog thereof (such as, for example, where the -O-C(O-) alkyl linking group and / or -O-O- alkyl linking group is / are independently C2 to C12)); (iii) polylactide group(s), (iv) polyglycolide group(s), (v) one or more poly ether group(s) (such as, for example, polyethylene group(s) (PEG group(s)) (or group(s) independently derived from a polyethene glycol (PEG) or polyethylene glycol (PEG) oligomer, a structural analog thereof, or the like,), a polypropylene group (or derived from a polypropylene glycol) (e.g.,or a structural analog thereof (e.g., -O-O- alkyl linking group is / are independently C2 or C3 or all C2 or C3) (e.g., where n is 1 tolOO, including all integer numbers and ranges therebetween); (vi) one or more polytetrahydrofuran group(s); (vii) one or more polycarbonate group(s);(viii) one or more polycarbonate diol group(s); (ix) one or more polycarbonate triol group(s), (x) one or more PDMS bisamine group(s) (or group(s) independently derived from a PDMS oligomer (such as, for example, a PDMS bis amine oligomer, a structural analog thereof, or the like)) (e.g.,structural analog thereof, where Z is O or NR, or a structural analog thereof (such as, for example, where the - Z-Si- alkyl linking group is independently C2 to C12, including all integer number of carbons therebetween or a structural analog thereof) (e.g., where n is 1 to 100, including all integer numbers and ranges therebetween), or a structural analog thereof, or the like.

[0056] A macromer can comprise various norbornene groups. In various examples, all of the norbomene groups are the same (e.g., structurally the same and / or compositionally the same). In various examples, two or more or all of the norbornene groups are different (e.g., structurally different and / or compositionally different). In various examples, at least a portion, substantially all or all of the norbornene group(s) independently comprise(s) the following structure:structural analog thereof, a stereoisomer thereof, an isotopic variant, or the like thereof, where L is a linking group. In various examples, L is independently an ester group (-C(O)O-) or an amide group (-C(O)NR-), where R is an H or an alkyl group)) or where two L groups taken together form a ring (such as, for example, ithe like).

[0057] A macromer can have various end groups. In various examples, a macromer comprises end groups independently chosen from carboxylic acid group (-C(O)OH), carboxylate group, ether groups, hydroxyl groups (-OH), amide groups, structural analogs thereof, and the like.

[0058] A macromer can have various amounts of norbomene groups. In various examples, a macromer comprises about 1 to about 20 norbomene groups (e.g., where at least a portion of, substantially all, or all of which are pendant norbornene groups), including all integer numbers of norbomene groups and ranges therebetween (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19).

[0059] An oligomer group (or a macromer) can have various molecular weights. In various examples, an oligomer group comprises (or the oligomer group(s) of a macromer independently comprise(s) (or a macromer comprises)) a molecular weight (Mw) of from about 200 g / mol to about 10,000 g / mol, including all 0.1 g / mol values and ranges therebetween. The molecular weight (Mw) of an oligomer group or groups (or a macromer) can be determined by methods known in the art. In various examples, the molecular weight (Mw) of an oligomer (or macromer) is determined by gel permeation chromatography (GPC), mass spectrometry, or the like, or any combination thereof.

[0060] An oligomer group (or a macromer) can comprise various numbers of repeat units. In various examples, an oligomer group (or a macromer) comprises about 3 to about 500 repeat units, including all integer number of repeat units and ranges therebetween. In various examples, all of the repeat units of an oligomer group (or a macromer) are substantially the same (e.g., substantially compositionally the same and / or substantially structurally the same) (e.g., with the exception of the presence of a norbomene group) or the same (e.g., compositionally the same and / or structurally the same). In various examples, at least two or more, at least three or more, etc. f the repeat units of an oligomer group (or a macromer) are different (e.g., with the exception of the presence of a norbornene group) same (e.g., compositionally different and / or structurally different).

[0061] In an aspect, the present disclosure provides methods of making macromers. In various examples, a method produces a macromer of the present disclosure. Non-limiting examples of methods of making macromers are disclosed herein.

[0062] In various examples, a method of making a macromer or macromers comprises: contacting one or more oligomer(s), one or more norbomene group precursor(s), optionally, one or more base catalyst(s), and optionally, one or more aliphatic epoxide(s) and / or one or more solvent(s) for a desired time and / or temperature and / or in a desired atmosphere, where the macromer(s) is / are formed. In various examples, a method of making a macromer or macromers comprises: holding for a desired time and / or temperature and / or in a desired atmosphere a reaction mixture comprising one or more oligomer(s), one or more norbornene group precursor(s), optionally, one or more base catalyst(s), optionally, one or more aliphatic epoxide(s), and optionally, one or more solvent(s), where the macromer(s) is / are formed.

[0063] In various examples, a method of making a macromer or macromers (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) of the present disclosure) comprises: forming a reaction mixture comprising; one or more oligomer(s), one or more norbornene group precursor(s), optionally, one or more base catalyst(s) (such as, forexample, caffeine, lidocaine, triethylamine, triphenylphosphine, structural analogs thereof, and the like) (e.g., at about 1 to about 10 mol% (relative to the moles of norbornene group precursor(s)), including all 0.1 mol% values and ranges therebetween), optionally, one or more aliphatic epoxide(s), and optionally, one or more solvent(s); and holding the reaction mixture (e.g., for a desired time and / or temperature and / or in a desired atmosphere), where the macromer(s) is / are formed.

[0064] In various examples, a method is catalyzed (such as, for example, by one or more base catalyst(s), which may independently be green catalysts). In various examples, a method comprises aminolysis or the like. In various examples, a method comprises aminolysis or the like and does not comprise a catalyst (such as, for example, a base catalyst or the like).

[0065] Typically, a synthesis tolerates moisture well, does not require purification, and does not generate toxic byproducts. It typically follows general principles of green chemistry.

[0066] Various oligomers can be used. In various examples, an oligomer is configured to form a macromer or oligomer group of the present disclosure. In various examples, an oligomer forms an oligomer group described herein. In various examples, an oligomer comprises a plurality of ether (e.g., polyether or the like) repeat units, a plurality of dimethylsilioxane repeat units (e.g., polydimethylsiloxane or the like) repeat units, or a structural analog thereof, or the like, or any combination thereof.

[0067] An oligomer can have various terminal groups. In various examples, a terminal group is an end group. In various examples, an oligomer comprises terminal groups independently chosen from hydroxyl group (-OH), amine group (-NH2), structural analogs thereof, and the like. In various examples, a macromer is formed by functionalization of at least a portion of, substantially all, or all of the terminal groups of the oligomer(s) used in a method.

[0068] Various norbomene group precursors can be used. In various examples, a norbomene group precursor is a functionalized norbomene compound. In various examples, a norbomene group precursor is a functionalized norbomene compound configured to react with an oligomer (e.g., a terminal group of an oligomer). In various examples, a norbornene group precursor is a functionalized norbomene compound configured to form a macromer of the present disclosure. Non-limiting examples of norbomene group precursors are included provided herein. Non-limiting examples of norbornene group precursors include carbic anhydride (CPMA), norbomyl halides (such as, for example, norbornyl fluoride, norbornyl chloride, norbomyl bromide, norbornyl iodide, a structural analog thereof, or the like, or a combination thereof), structural analogs thereof, and the like, and any combination thereof.

[0069] Various amounts of oligomer(s) and / or norbornene group precursors(s) can be used. In various examples, oligomer(s) is / are present (e.g., individually or in the aggregate) at about 0.2 to about 1 equivalent or more (relative to norbomene group precursors), including all 0.1 equivalent values and ranges therebetween.

[0070] Various base catalysts can be used. In various examples, a single base catalyst is used. Combinations of catalysts may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different) base catalysts are used. In various examples, a base catalyst catalyzes a reaction between an oligomer or oligomers and a norbomene group precursor or norbornene group precursors. Non-limiting examples of base catalysts include caffeine, lidocaine, triethylamine, triphenylphosphine, structural analogs thereof, and the like, and any combination thereof.

[0071] Various amounts of base catalyst(s) can be used. In various examples, the base catalyst(s) is / are present (e.g., individually or in the aggregate) at about 1 to about 10 mol% (relative to the moles of norbomene group precursor(s)), including all 0.1 mol% values and ranges therebetween.

[0072] In various examples, at least a portion of a macromer (e.g., one or more oligomer group(s)) is formed in situ during macromer synthesis. In various examples, one or more oligomer group(s) is / are formed in situ during macromer synthesis by caffeine catalyzed in tandem ring-opening (CITRO). In various examples, a reaction mixture comprises about 1 to about 10 mol% caffeine (relative to the moles of norbornene group precursor(s)), including all 0.1 mol% values and ranges therebetween. Without intending to be bound by any particular theory, it is considered that addition of caffeine to the reaction mixture can increase the degree of norbomene group substitution. In the presence of caffeine, an aliphatic epoxide can be ring-opened by the carboxylic acid chain end of a macromer to yield slow-degrading materials, a process referred to as caffeine catalyzed in tandem ring-opening (CITRO). Nonlimiting examples of aliphatic epoxides include propylene oxide, 1,2-epoxybutane, 1,2- epoxyhexane, epoxidized soybean oil, structural analogs thereof, and the like, and any combination thereof.

[0073] Various solvents may be used. In various examples, a single solvent is used. A combination of solvents may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different and / or functionally different) solvents are used. In various examples, a solvent or solvents form an azeotrope with water. Nonlimiting examples of solvents include hydrocarbons (such as, for example, octane, structural analogs thereof, and the like, and any combination thereof), alkyl benzenes (such as, forexample, toluene, xylenes, structural analogs thereof, and the like, and any combination thereof), structural analogs thereof, and the like, and any combination thereof.10074] A method (e.g., a contacting, a holding or the like) can be performed under various reaction conditions. A method (e.g., a contacting, a holding, or the like) can comprise one or more step(s) and each step can be performed under the same or different reaction conditions as other steps. A method (e.g., a contacting, a holding, or the like) can be carried out at various temperatures. In various examples, a polymerization reaction is carried out at about room temperature (e.g., from about 20 °C to about 30 °C, including all 0.1 °C values and ranges therebetween), or above room temperature (e.g., above room temperature up to or about a boiling point of the solvent(s), if present) (e.g., room temperature to about 150 °C or above, or any combination thereof (e.g., where each irradiation, polymerization reaction, or the like) is performed at a different temperature as other steps). In various examples, a method (e.g., an irradiation, polymerization reaction, or the like) is carried out at about 20 °C to about 150 °C, including all 0.1 °C values and ranges therebetween.

[0075] A method (e.g., a contacting, a holding, or the like) can be carried out at various pressures. In various examples, a method (e.g., a contacting, a holding, or the like) is carried out at atmospheric pressure (e.g., 1 standard atmosphere (atm) at sea level), at greater than atmospheric pressure (e.g. heating in a sealed pressurized reaction vessel and the like), at below atmospheric pressure (e.g., under vacuum (e.g., from about 1 mTorr or less to about 100 mTorr or less, including all 0.1 mTorr values and ranges therebetween) (e.g., about 100 mTorr or less, about 50 mTorr or less, about 10 mTorr or less, or about 1 mTorr or less) and the like), or any combination thereof (e.g., where each step is performed at a different pressure as other steps).

[0076] A method (e.g., a contacting, a holding, or the like) can be carried out for various times. The reaction time can depend on factors such as, for example, temperature, desired conversion of oligomer(s) and / or norbomene group precursor(s), concentration of oligomer(s) and / or norbornene group precursor(s) and / or base(s), if present, or the like, or any combination thereof. In various examples, reaction times range from about seconds (e.g., about 10 seconds) to greater than about 24 hours, including all integer second values and ranges therebetween, or any combination thereof (e.g., where each step is performed at the same time or a different time as other steps).

[0077] In an aspect, the present disclosure provides compositions. In various examples, composition comprises one or more macromer(s) of the present disclosure. In various examples, a composition is a resin (such as, for example, a printing resin (e.g., a 3-D printingresin) or the like) or the like. In various examples, a composition is used in a method of the present disclosure. Non-limiting examples of compositions are disclosed herein.10078] In various examples, a composition comprises one or more macromer(s) (e.g., functionalized macromer(s), norbomene-functionalized macromer(s), or the like). In various examples, a composition (e.g., a photopolymerizable composition or the like) further comprises one or more crosslinker(s); one or more photoadditive(s) and / or one or more thermal additive(s); and optionally, one or more solvent(s) (e.g., diluent(s) or the like). In various examples, a composition is capable of thermal crosslinking, photochemical crosslinking, or the like, or both (or configured to be of thermally crosslinked, photochemically crosslinked, or the like, or both). In various examples, the macromer(s) (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)), crosslinker(s), one or more photoadditive(s) and / or one or more thermal additive(s), optionally, one or more solvent(s) (e.g., diluent(s) or the like) are the only functional components of the composition (e.g., components involved in function of the composition as a printing resin (e.g., as described herein). In various examples, a composition consists essentially of macromer(s), crosslinking group(s), one or more photoadditive(s) and / or one or more thermal additive(s); and optionally, one or more solvent(s) (e.g., diluent(s) or the like). In various examples, a composition does not comprise any components that materially affect its function as a resin (e.g., a 3D printing resin or the like) or the like. In various examples, the macromer(s) (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)), crosslinker(s), photoadditive(s), optionally, one or more solvent(s) (e.g., diluent(s) or the like) make up 100% of the composition.

[0079] A composition can comprise various amounts of macromers. In various examples, the macromer(s) is / are present (e.g., individually or in the aggregate) at about 50 to about 99 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 50 to about 90 wt.%, about 45 to about 55 wt.%, about 52 wt.%).

[0080] A composition can comprise various amounts of crosslinkers. A composition may comprise two or more different (e.g., structurally and / or compositionally different) crosslinkers. In various examples, a crosslinker or crosslinkers is / are a multifunctional crosslinker(s) (such as, for example, bifunctional crosslinker(s) or the like. In various examples, a crosslinker can react in a thio-ene reaction with a norbornene group of a macromer. Non-limiting examples of crosslinkers include thiols (such as, for example, thiols comprising two or more thiol groups), dithiolanes and derivatives thereof, structural analogsthereof, and the like, and any combination thereof. Non-limiting examples of thiols include pentaerythritol tetrakis(3 -mercaptopropionate), trimethylolpropane tris(3- mercaptopropionate), 2,2'-(Ethylenedioxy)diethanethiol, lipoate esters, secondary thiols (such as, for example, KarenzMT™ and structural analogs thereof, and the like, and any combination thereof), and structural analogs thereof, and the like.

[0081] A composition can comprise various amounts of crosslinkers. In various examples, a crosslinker or crosslinkers is / are present (e.g., individually or in the aggregate) at about 5 to about 20 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 25 to about 40 wt.%, about 33 wt.%).

[0082] In various examples, a composition is an off-stoichiometric composition (such as, for example, an off-stoichiometric photopolymer or the like). In various examples, an off- stoichiometric composition comprises a molar excess of norbomene groups (e.g., about 1% to about 50%) relative to the moles of crosslinker (e.g., thiol or the like).

[0083] A composition can comprise various photoadditives and / or thermal additive(s). A photoadditive may be a thermal additive, and vice versa. In various examples, a photoadditive, on irradiation with electromagnetic radiation of an appropriate wavelength or wavelengths, generates one or more radical specie(s) suitable for reaction of macromer(s) and / or crosslinker(s) and / or, if present, one or more monomer(s). In various examples, a photoadditive can absorb at least a portion of the electromagnetic radiation (e.g., used to form an object, an article of manufacture, or the like. In various examples, a thermal initiator on heating to an appropriate temperature generates one or more radical specie(s) suitable for reaction of macromer(s) and / or crosslinker(s) and / or, if present, one or more monomer(s). A composition may comprise two or more different (e.g., structurally and / or compositionally different and / or functionally different) photoadditives and / or thermal additives. In various examples, at least one photoadditive is a photoinitiator or the like and / or at least one thermal additive is a thermal initiator or the like. Non-limiting examples of photoadditives include photoinitiator(s), photoabsorbers (such as, for example, UV absorber(s) or the like), stabilizer(s), and the like, and any combination thereof. Non-limiting examples of thermal additives include thermal initiator(s), photoabsorbers (such as, for example, UV absorber(s) or the like), stabilizer(s), and the like, and any combination thereof. Without intending to be bound by any particular theory, it is considered a photoinitiator or photoinitiators and / or a thermal initiator or thermal initiators initiate(s) the radical thiol-norbomene crosslinking, photoabsorber(s) (such as, for example, UV absorber(s) or the like) limit(s) the UV penetration depth and / or increase(s) the z resolution of the irradiation; and stabilize^ s)reduce(s) or prevent(s) premature curing and prolong(s) the composition shelf life. Nonlimiting examples of photoinitiators, which may also be thermal initiators, include diphenyl (2,4,6-trimethylbenzoyl)- phosphine oxide (TPO), Omnirad TPO-L, phenylbis(2,4,6- trimethylbenzoyl)phosphine oxide, lithium phenyl-2,4,6-trimethylbenzoylphosphinate, 2,2- dimethoxy-2-phenylacetophenone, camphorquinone, structural analogs thereof, and the like, and any combination thereof. Non-limiting examples of thermal initiators include azobisisobutyronitrile, l,l'-azobis(cyclohexanecarbonitrile), potassium persulfate, di -tertbutyl peroxide, benzoyl peroxide, structural analogs thereof, and the like, and any combination thereof. Non-limiting examples of photoabsorbers (such as, for example, UV absorber(s) or the like) include 2,5-bis(5-tert-butyl-benzoxazol-2-yl)thiophene (BBOT), Sudan red, orange / yellow food dye, structural analogs thereof, and the like, and any combination thereof. Non-limiting examples of stabilizers include butylated hydroxytoluene, Vitamin E, pyrogallol, 2,2,6,6,-tetramethylpiperidin-l-yl)oxyl (TEMPO), caffeic acid, catechol, 4- methoxyphenol, structural analogs thereof, and the like, and any combination thereof.

[0084] A composition can comprise various amounts of photoadditives and / or thermal additives. In various examples, a photoadditive or photoadditives is / are present (e.g., individually or in the aggregate) at about 0.001 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s) or the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.005 to about 2 wt.%, about 0.01 to about 3 wt.%, about 0.01 to about 3 wt.%, about 33 wt.%). In various examples, a photoinitiator / photoinitiators and / or stabilizer / stabilizers is / are present (e.g., individually or in the aggregate) at about 0.01 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s) or the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.05 to about 2 wt.%, about 1 wt.%, or less than 1 wt.%). In various examples, a photoabsorbers or photoabsorbers (such as, for example, UV absorber(s) or the like) is / are present (e.g., individually or in the aggregate) at about 0.01 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s) or the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.005 to about 0.01 wt.%, about 0.05%, or less than 0.05 wt.%).

[0085] A composition can comprise various amounts of diluents. A composition may comprise two or more different (e.g., structurally and / or compositionally different and / or functionally different) diluents. Non-limiting examples of diluents include reactive diluents (such as, for example, divinyl triethylene glycol, trimethylolpropane diallyl ether, limonene, propargyl alcohol, structural analogs thereof, and any liquid with one or more thiol -reactiveunsaturated bonds, and the like, and any combination thereof) and diluents (such as, for example, propylene carbonate, ethylene glycol, dimethyl sulfoxide, ethyl acetate, acetone, structural analogs thereof, and the like, and any combination thereof.

[0086] A composition can comprise various amounts of diluents. In various examples, a diluent or diluents is / are present (e.g., individually or in the aggregate) at about 1 to about 20 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.005 to about 0.01 wt.%, about 0.05%, or less than 0.05 wt.%).

[0087] A composition may comprise various solvents. In various examples, a single solvent is used. A combination of solvents may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different and / or functionally different) solvents are used. Non-limiting examples of solvents include water, hydrocarbons (such as, for example, hexane, octane, structural analogs thereof, and the like, and any combination thereof), ketones (such as, for example, acetone, structural analogs thereof, and the like, and any combination thereof), alkyl benzenes (such as, for example, toluene, xylene, structural analogs thereof, and the like, and any combination thereof), halogenated analogs thereof, halogenated solvents, structural analogs thereof, and the like, and any combination thereof. In various examples, one or more solvent(s) make up the remainder of a composition.

[0088] In various examples, a composition is an emulsion. In various examples, an emulsion is a high internal phase emulsion (HIPE) or the like.

[0089] In various examples, a composition (which may be an emulsion or the like) further comprises one or more thickener(s) and / or emulsifier(s). Non limiting examples of thickeners include hyaluronic acid, chondroitins (such as, for example, chondroitin sulfates, structural analogs thereof, and the like), dextrans, starches, structural analogs thereof, and the like, and any combination thereof. Non limiting examples of emulsifier(s) include non-ionic surfactants (such as, for example, sorbitan monooleates (e.g., SPAN® 80, structural analogs thereof, and the like), poloxamers (such as, for example, block copolymers with a triblock structure (PEO-PPO-PEO) comprising hydrophilic poly(ethylene oxide) (PEO) and hydrophobic polypropylene oxide) (PPO) chains (e.g., Pluronics®), structural analogs thereof, and the like, and any combination thereof. In various examples, a thickener or thickeners and / or an emulsifier or emulsifiers is / are present in composition (which may be an emulsion or the like) (e.g., individually or in the aggregate) at about 0 to about 10 wt.% (relative to the total weight of thickener(s) and / or emulsifier(s) and water), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.001 to about 10 wt.%).

[0090] In various examples, a composition (which may be an emulsion or the like) comprises water, one or more organic solvent(s) (such as, for example, organic solvent(s) with low, negligible, or no (e.g., no observable, such as, for example, by an analytical method, such as, for example, nuclear magnetic resonance, chromatography (e.g., high performance liquid chromatography, or the like), or the like, or any combination thereof) solubility in water), and, optionally, one or more thickener(s) and / or emulsifier(s). In various examples, a composition (which may be an emulsion or the like) comprises water, one or more organic solvent(s) chosen from hydrocarbon solvents (such as, for example, hexane, octane, toluene, xylene, structural analogs thereof, and the like, and any combination thereof), structural analogs thereof (such as, for example, halogenated analogs thereof), and the like, and any combination thereof, and optionally, one or more thickener(s).

[0091] A composition (which may be an emulsion) may comprise various amounts of water and organic solvent(s). In various examples, a composition (which may be an emulsion) comprises an oil (e.g., macromer(s), crosslinker(s), and the like, and any combination thereof) : water volume ratio of about 1 : about 99 (about 0.01) to about 60 : about 40 (aboutl.5), including all 0.001 ratio values and ranges therebetween (e.g., about 5 : about 95 to about 60 : about 40, about 10 : 90 to about 60 about 40, about 5 : about 95 to about 25 : about 75, about 5 : about 95 to about 30 : about 70, about 10 : about 90 to about 25 : about 75, about 10 : about 90 to about 30 : about 70, about 5 : about 95 to about 50 : about 50, or about 5 : about 95 to about 40 : about 60).

[0092] In various examples, a composition is an oil-in-water emulsion (e.g., where the oil dispersed phase comprises a portion of, substantially all, or all the macromer(s) (e.g., functionalized macromer(s), norbomene-functionalized macromer(s), or the like) and / or a portion of, substantially all, or all the crosslinker(s) and / or a portion of, substantially all, or all the photoadditive(s) and / or a portion of, substantially all, or all the non-water solvent(s) (e.g., diluent(s) or the like), if present). In various examples, an emulsion is formed by mixing (e.g., by rapid mixing or the like) water (e.g., an aqueous mixture comprising water and one or more thickeners(s).

[0093] In an aspect, the present disclosure provides methods of making an object (e.g., a three-dimensional object or the like), an article of manufacture, or the like of the present disclosure. In various examples, a method uses one or more composition(s) of the present disclosure. Non-limiting examples of methods of making macromers are disclosed herein.

[0094] In various examples, a method of forming an object (e.g., a three-dimensional object or the like), an article of manufacture, or the like is an additive manufacturing method.In various examples, an additive manufacturing method is a 3-D printing method or the like. In various examples, a 3-D printing method is digital light processing (DLP), stereolithography (SLA), volumetric printing, UV inkjet printing, two-photon polymerization printing, or the like.

[0095] In various examples, an object is a three-dimensional object or comprises one or more three-dimensional feature(s) or the like. Non -limiting examples of object and articles of manufacture include porous scaffolds, surgical prostheses, wearable electronics object or devices, earbud inserts (which may be custom earbud inserts, and microfluidic devices, or the like, or a portion thereof.

[0096] An object, an article of manufacture, or the like may be porous and / or comprise an interpenetrating network. In various examples, an object, an article of manufacture, or the like comprises a porosity and / or interpenetrating network as described herein. In various examples, a porous object, article of manufacture, or the like is made using a composition that is an emulsion or the like.

[0097] In various examples, a method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like comprises irradiating (e.g., with electromagnetic radiation, such as, for example, UV radiation (which may comprise one or more wavelength(s) from about 100 nanometers (nm) to about 450 nm, including all 0.1 nm wavelength values and ranges therebetween (e.g., about 350 to about 450 nm)) at least a portion (e.g., a desired portion) or all of a monolith comprising one or more composition(s) of the present disclosure (e.g., such that the object, the article of manufacture, or the like is formed). In various examples, an object, an article of manufacture, or the like comprises (or is) an elastomer (such as, for example, a soft elastomer or the like) or the like. In various examples, a plurality of crosslinking groups (e.g., thioether groups or the like) are formed in the at least a portion or all of the at least a portion (e.g., a desired portion) or all of the monolith comprising the one or more composition(s) of the present disclosure macromer(s).

[0098] A monolith can have various forms. In various examples, a monolith comprises substantially the appropriate dimensions (the determination of which are within the purview of one of ordinary skill in the art) of the target object, article of manufacture, or the like. In various examples, a monolith is a film, an object (such as, for example, a 3 -dimensional object or the like), or the like.

[0099] In various examples, each crosslinking group (e.g., thioether group or the like) is formed by photoreaction of two or more of the norbornenyl groups with a crosslinker (e.g., a multifunctional thiol, such as, for example, a dithiol or the like) in the at least a portion or allof the at least a portion (e.g., a desired portion) or all of the monolith comprising the one or more composition(s) of the present disclosure macromer(s). In various examples, about 10% to about 100%, including all 0.1% values and ranges therebetween) of the norbomenyl groups of the macromer(s) is photoreacted to form the plurality of crosslinking groups.

[0100] Various electromagnetic radiation sources and wavelengths can be used. In various examples, electromagnetic radiation is provided by a lamp or lamps, a bulb or bulb, a laser or lasers, a light-emitting diode or light emitting diodes, or the like, or any combination thereof. In various examples, the electromagnetic radiation comprises one or more wavelength(s) of about 100 nm to about 700 nm, including all 0.1 nm values and ranges therebetween (e.g., about 200 nm to about 700 nm, about 385, or about 405 nm).

[0101] Irradiating may be patterned. In various examples, irradiating at least a portion, substantially all, or all of a monolith comprising one or more composition(s) of the present disclosure with the electromagnetic radiation is carried out in predetermined pattern. In various examples, the irradiating at least a portion, substantially all, or all of a monolith comprising one or more composition(s) of the present disclosure with the electromagnetic radiation is carried lithographically, in a direct write mode, or the like.

[0102] Thermal treatment can be carried under various conditions. In various examples, a thermal treatment comprises heating a monolith (which may have been previously irradiated or thermally treated) to a temperature that results in formation of crosslinking groups (or additional crosslinking groups). In various examples, heating is carried out at (such as, for example, in a bath, an oven, or the like) a temperature of about 30 to 100 degrees Celsius (°C), including all 0.1 °C values and ranges therebetween, and / or for about 1 minute to about 150 minutes, including all 0.1 minuet values and ranges therebetween.

[0103] Irradiating and / or thermally treating may be repeated a desired number of times. In various examples, at least a portion or all the contacting(s) or the irradiating(s) and / or thermal treatment(s), or both, is / are carried out with the composition(s). In various examples, at least a portion or all the contacting(s) or the irradiating(s) and / or thermal treatment(s), or both, is / are carried out with one or more different (e.g., compositionally different, different concentration, or the like) composition(s).

[0104] In various examples, a method of forming an object further comprises forming a film or the like (such as, for example, from the composition(s) or the like). In various examples, the film or the like is formed prior to and / or during the irradiating with electromagnetic radiation of the composition(s) or the like.

[0105] An irradiated product or thermally treated product may be subjected to various post-irradiation or post thermal treatment processes. Non-limiting examples of postirradiation or post thermal treatment processes include additional irradiation and / or thermal treatmen t(s), solvent (e.g., water, alcohols (such as, for example, ethanol, structural analogs thereof, and the like), and any combination thereof), washing, drying (which may be vacuum drying, freeze drying, or the like), and the like, and any combination thereof.

[0106] In various examples, an irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product is subjected to an interpenetrating network formation process. In various examples, an irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product is contacted with (e.g., a reaction mixture comprising) one or more monomer(s) and, optionally, one or more monomer crosslinkers, and one or more photoinitiator(s) and / or thermal initiator(s) (suitable, non-limiting examples of which are disclosed herein); holding (e.g., for a time and / or temperature) the contacted irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product (e.g., until the contacted irradiated product or thermally treated product or otherwise postprocessed irradiated product or thermally treated product is swollen (such as, for example, swollen to equilibrium); irradiating and / or thermally treating the contacted and held irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product, where an interpenetrating network is formed (e.g., the irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product comprises an interpenetrating network).

[0107] In various examples, the monomer(s) and crosslinker(s) are able to form an interpenetrating network (e.g., by photochemical polymerization, thermal polymerization, or the like, or any combination thereof). In various examples, the monomer(s) are able to form an interpenetrating network comprising a first network comprising the polymerized and crosslinked monomer(s) and a second network comprising the reacted macromer(s). In various examples, a first network is at least partially, substantially, or completely formed first (e.g., by irradiation or thermal treatment) and a second network is formed after the first network is at least partially, substantially, or completely formed (e.g., by irradiation or thermal treatment, which may be the same or different that the irradiation or the thermal treatment used to form the first network). In various examples, a second network is at least partially, substantially, or completely formed (e.g., by irradiation or thermal treatment) first and a first network is formed after the second network is at least partially, substantially, orcompletely formed (e.g., by irradiation or thermal treatment, which may be the same or different that the irradiation or the thermal treatment used to form the second network). 10108] In various examples, an irradiated product or thermally treated product or otherwise post-processed irradiated product or thermally treated product is contacted with a reaction mixture comprising one or more monomer(s) (e.g., where the monomer(s) is / are present (e.g., individually or in the aggregate) at about 80 to about 99.5 wt.% (relative to the total weight of the reaction mixture)), including all 0.1 wt.% values and ranges therebetween (e.g., about 90 to about 99.5 wt.%); one or more monomer crosslinker(s) (e.g., where the monomer crosslinker(s) is / are present (e.g., individually or in the aggregate) at about 0.1 to about 1 wt.% (relative to the total weight of the monomer(s)), including all 0.1 wt.% values and ranges therebetween; one or more photoinitiator(s) and / or one or more thermal initiator(s) (e.g., where the photoinitiator(s) and / or thermal initiator(s) is / are present (e.g., individually or in the aggregate) at about 0.1 to about 2 wt.% (relative to the total weight of the monomer(s))), including all 0.1 wt.% values and ranges therebetween; and, optionally, one or more solvent(s) (e.g., organic solvents, such as, for example, hydrocarbons (such as, for example, hexane, octane, structural analogs thereof, and the like, and any combination thereof), alcohols (such as, for example, methanol, ethanol, structural analogs thereof, and the like, and any combination thereof), ketones (such as, for example, acetone, structural analogs thereof, and the like, and any combination thereof), alkyl benzenes (such as, for example, toluene, xylene, structural analogs thereof, and the like, and any combination thereof), halogenated analogs thereof, halogenated solvents, structural analogs thereof, and the like, and any combination thereof). In various examples, one or more solvent(s) make up the remainder of a reaction mixture.

[0109] Non-limiting examples of monomers include acrylate monomers (such as, for example, methyl acrylate, ethyl acrylate, butyl acrylates, isobomyl acrylate, urethane acrylates, structural analogs thereof, and the like), methacrylate monomers (such as, for example, methyl methacrylate, ethyl methacrylate, hydroxyethyl methacrylate, urethane methacrylate, structural analogs thereof, and the like), vinyl monomers (such as, for example, styrene, N-vinyl pyrrolidone, vinyl imidazoles, structural analogs thereof, and the like), structural analogs thereof, and the like, and combination thereof. Non-limiting examples of monomer crosslinkers include acrylate crosslinkers (which may be diacrylate crosslinkers or the like) (such as, for example, butanediol diacrylate, PEG diacrylate, hexandiol diacrylate, pentaerythritol tetraacrylate, structural analogs thereof, and the like), dimethacrylate crosslinkers (such as, for example, ethylene glycol dimethacrylate, diurethane dimethacrylate,structural analogs thereof, and the like), divinyl crosslinkers (such as, for example, diethylene glycol divinyl ether, butanediol divinyl ether, structural analogs thereof, and the like), bifunctional and multifunctional thiol crosslinkers, structural analogs thereof, and the like, and combination thereof

[0110] In various examples, a method of forming an object, an article of manufacture, or the like further comprises functionalizing the object, the article of manufacture, or the like. A non-limiting example of functionalizing is shown in FIG. 3(E). In various examples, at least a portion, substantially all, or all of a surface or surfaces of an object or an article of manufacture are functionalized (such as, for example, surface functionalized or the like). In various examples, an object, an article of manufacture, or the like comprises norbornene groups (at least a portion or all of which may be surface norbomene groups) (which may be configured or available for click chemistry modification (such as, for example, with one or more compound(s) comprising one or more thiol group(s) (e.g., cysteamine (such as, for example to convert unreacted norbomenes to amines or the like), peptides containing cysteine, thiol-functionalized sugars, structural analogs thereof, and the like), with compound(s) comprising one or more tetrazine group(s), structural analogs thereof, and the like, or any combination thereof). In various examples, a functionalizing an object, an article of manufacture, or the like comprises one or more click reaction(s) independently between one or more norbornene group(s) (at least a portion or all of which may be surface norbomene groups) (which may be configured or available for click chemistry modification) and a clickable compound or the like (e.g., one or more compound(s) comprising one or more thiol group(s) (e.g., cysteamine, peptides containing cysteine, thiol-functionalized sugars, structural analogs thereof, and the like), with compound(s) comprising one or more tetrazine group(s), structural analogs thereof, and the like, or any combination thereof).10111] In an aspect, the present disclosure provides objects and articles of manufacture. In various examples, an object or an article of manufacture comprises one or more irradiated and / or thermally treated composition(s) of the present disclosure. Non-limiting examples of uses of objects and articles of manufacture are disclosed herein.

[0112] In various examples, an object or an article of manufacture comprises one or macromer(s) (e.g., functionalized macromer(s) or norbomene-functionalized macromer (s)) of the present disclosure. In various examples, one or more of the macromer(s) (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) is / are cross-linkable and / or one or more at least partially, substantially, or completely crosslinked macromer(s)(e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) of the present disclosure.

[0113] In various examples, an object (e.g., a three-dimensional object or the like), comprises one or more three-dimensional feature(s), or the like, or any combination thereof. In various examples, an object is a vascular graft (such as, for example, an aortic arch or the like) or the like, which may be porous. Non-limiting examples of articles of manufacture include porous scaffolds, at least a part or portion of a surgical prosthesis, at least a part or portion of a wearable electronic object or device, at least a part or portion of an earbud insert (which may be a custom earbud insert), or at least a part or portion of a microfluidic device, or the like.

[0114] An object, an article of manufacture, or the like may be porous. In various examples, an object, an article of manufacture, or the like comprises one or more porous regions (e.g., one or more or all of which are interior regions or the like). In various examples, an object, an article of manufacture, or the like comprises one or more porous regions (e.g., one or more or all of which are interior regions or the like) and non-porous regions. In various examples, an object, an article of manufacture, or the like comprises about 40 vol.% to about 99 vol.% porosity, including all 0.1 vol.% porosity values and ranges therebetween (e.g., about 40 vol.% to about 95 vol.% porosity, about 40 vol.% to about 90 vol.% porosity, about 50 vol.% to about 90 vol.% porosity, or about 70 vol.% to about 90 vol.% porosity) and / or a plurality of pores (e.g., where a portion, substantially all, or all of the pores are interconnected) comprising a size (e.g., a linear dimension, which may be a longest linear dimension, or the like) of about 1 micron to about 200 microns, including all 0.1 micron values and ranges therebetween (e.g., about 1 micron to about 100 microns, about 1 micron to about 100 microns, or about 5 microns to about 200 microns). Porosity and / or pore size can be determined by methods known in the art. In various examples, porosity and / or pore size is / are determined by electron microscopy (such as, for example, scanning electron microscopy, and the like), x-ray micro-computed tomography (micro-CT), and the like, and any combination thereof.

[0115] An object, an article of manufacture, or the like may comprise an interpenetrating network. In various examples, an object, an article of manufacture, or the like may comprise an interpenetrating network comprising a first network (e.g., about 10 wt.% to about 70 wt.% (relative to the total weight of the object, the article of manufacture, or the like), including all 0.1 wt.% values and ranges therebetween) comprising one or more at least partially crosslinked polymer(s) (which may be formed as described herein) and a second network(e.g., about 30 wt.% to about 90 wt.% (relative to the total weight of the object, the article of manufacture, or the like), including all 0.1 wt.% values and ranges therebetween) comprising reacted (e.g., at least partially, substantially, or completely crosslinked) macromer(s), where the two networks are interpenetrating networks. Non-limiting examples of at least partially crosslinked polymers include at least partially crosslinked polyacrylates, at least partially crosslinked polymethacrylates, least partially crosslinked polystyrenes, least partially crosslinked poly(N-vinyl pyrrolidone)s, least partially crosslinked polyaimidazoles, copolymers thereof, structural analogs thereof, and the like and any combination thereof. In various examples, an object, an article of manufacture, or the like may comprise an interpenetrating network and exhibit increased toughness, slower crack propagation, or the like, or any combination thereof relative the substantially same or same object, article of manufacture, or the like that does not comprise an interpenetrating network

[0116] The following Statements provide examples of macromers and compositions, methods of making macromers, methods of making objects and articles of manufacture, and objects and articles of manufacture of the present disclosure:Statement 1. A macromer (e.g., a functionalized macromer or norbornene-functionalized macromer) comprising one or more (e.g., two or more) norbomene groups (e.g., pendant norbomene groups or the like) (e.g., a macromer comprising one or more oligomer group(s), each oligomer group comprising one or more pendant norbomene group(s)).Statement 2. A macromer according to Statement 1, comprising (or the oligomer group(s) independently comprise) the following structure:OG-(-NBG)x, where OG is an oligomer group, NBG is a norbornene group, and x is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, etc. .Statement 3. A macromer according to Statement 1 or 2, where each oligomer group is formed from (or derived from) an oligomer group comprising a plurality of ether repeat units (e.g., polyether or the like), dimethylsilioxane repeat units (e.g., polydimethylsiloxane or the like) repeat units, or a structural analog(s) thereof, or a combination thereof.Statement 4. A macromer according to any one of the preceding Statements, where the oligomer group(s) independently comprise(s): one or more polyhydroxyalkanoate(s), one or more poly caprolactone (PCL) diol group(s) (or group(s) independently derived from a PCL diol oligomer) (e.g.,or a structural analog thereof, where n is independently 1 to 100, including all integer numbers and ranges therebetween) or a structural analog thereof (such as, for example, where the -O- C(O-) alkyl linking group and / or -O-O- alkyl linking group is / are independently C2 to C12)), polylactide group(s), polyglycolide group(s), one or more polyether group(s) (such as, for example, polyethylene group(s) (PEG group(s)) (or group(s) independently derived from a polyethene glycol (PEG) or polyethylene glycol (PEG) oligomer, a structural analog thereof, or the like), a polypropylene glycol group (or derived from a polypropylene glycol) (e.g.,or a structural analog thereof (e.g., -O-O- alkyl linking group is / are independently C2 or C3 or all C2 or C3), where n is 1 to 100, including all integer numbers and ranges therebetween), one or more polytetrahydrofuran group(s), one or more polycarbonate group(s), one or more polycarbonate diol group(s), one or more polycarbonate triol group(s), one or more PDMS bisamine group(s) (or group(s) independently derived from a PDMS oligomer (such as, for example, a PDMS bis amine oligomer, a structural analog thereof, or the like)structural analog thereof, where Z is O or NR and / or n is 1 to 100, including all integer numbers and ranges therebetween, or a structural analog thereof (such as, for example, where the -Z-Si- alkyl linking group is independently C2 to C12)), or a structural analog thereof, or a structural analog thereof, or the like.Statement 5. A macromer according to any one of the preceding Statements, where the norbomene group(s) (at least a portion of, substantially all, or all of which may be pendant norbomene groups) independently comprise(s) the following structure:structural analog thereof, a stereoisomer thereof, an isotopic variant, or the like thereof, where L is a linking group (such as for example, an ester group (-C(O)O-) or an amide group (-C(O)NR-), where R is an H or an alkyl group) or where two L groups taken together form a ring (such as, for example, ir the like).Statement 6. A macromer according to any one of the preceding Statements, where the oligomer group(s) independently comprise(s) a molecular weight (Mw) (which may be determined by gel permeation chromatography (GPC) or the like) of about 200 g / mol to about 10,000 g / mol, including all 0.1 g / mol values and ranges therebetween.Statement 7. A method of making a macromer or macromers (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) of the present disclosure or one or more macromers(s) (e.g., functionalized macromer (s) or norbornene-functionalized macromer (s) according to any one of Statements 1 to 6) comprising: forming a reaction mixture comprising; one or more oligomer(s) (e.g., oligomer(s) independently comprising a plurality of ether repeat units (e.g., polyether or the like), a plurality of dimethylsilioxane repeat units (e.g., polydimethylsiloxane or the like), or a structural analog thereof, or the like, or any combination thereof, and one or more norbornene group precursor(s) (e.g., carbic anhydride (CPMA), norbomyl halides (such as, for example, norbornyl fluoride, norbornyl chloride, norbomyl bromide, norbornyl iodide, a structural analog thereof, or the like, or a combination thereof), structural analogs thereof, and the like, and any combination thereof), optionally, one or more base catalyst(s) (such as, for example, caffeine, lidocaine, triethylamine, triphenylphosphine, structural analogs thereof, and the like) (e.g., at about 1 to about 10 mol% (relative to the moles of norbornene group precursor(s)), including all 0.1 mol% values and ranges therebetween), and optionally, one or more aliphatic epoxide(s); and holding the reaction mixture (e.g., for a desired time and / or temperature and / or in a desired atmosphere), where the macromer(s) is / are formed.Statement 8. A composition (e.g., a photopolymerizable composition or the like) (which may be an emulsion (e.g., where the composition further comprises water, optionally, one or more solvent(s) chosen from hydrocarbons (such as, for example, hexane, octane, structuralanalogs thereof, and the like, and any combination thereof), ketones (such as, for example, acetone, structural analogs thereof, and the like, and any combination thereof), alkyl benzenes (such as, for example, toluene, xylene, structural analogs thereof, and the like, and any combination thereof), halogenated analogs thereof, structural analogs thereof, halogenated solvents, and the like, and any combination thereof, and one or more thickener(s) and / or one or more emulsifier(s))) (e.g., capable of thermal crosslinking, photochemical crosslinking, or the like, or both (or configured to be of thermally crosslinked, photochemically crosslinked, or the like, or both) comprising one or more macromer(s) (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) of the present disclosure (e.g., functionalized macromer (s) or norbornene-functionalized macromer (s) according to any one of Statements 1 to 6) and / or one or more macromer(s) made by a method of the present disclosure (e.g., macromer(s) made by a method of Statement 7).Statement 9. A composition (e.g., a photopolymerizable composition or the like) according to Statement 7, further comprising one or more crosslinker(s); one or more photoadditive(s) (e.g., where at least one of the photoadditives is a photoinitiator or the like) and / or one or more thermal additives (e.g., where at least one of the thermal additives is a thermal initiator or the like); and optionally, one or more solvent(s) (e.g., diluent(s) or the like).Statement 10. A composition according to Statement 8 or 9, where the macromer(s) is / are present (e.g., individually or in the aggregate) at about 50 to about 99 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 50 to about 90 wt.%, about 45 to about 55 wt.%, about 52 wt.%).Statement 11. A composition according to Statement 9 or 10, where the crosslinking(s) is / are chosen from thiols (such as, for example, thiols comprising two or more thiol groups), dithiolanes and derivatives thereof, structural analogs thereof, and the like, and any combination thereof.Statement 12. A composition according to any one of Statements 9 or 11, where the crosslinker(s) is / are present (e.g., individually or in the aggregate) at about 5 to about 20 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 25 to about 40 wt.%, about 33 wt.%).Statement 13. A composition according to any of Statements 9 to 12, where the photoadditive(s) is / are chosen from photoinitiator(s), photoabsorbers (such as, for example, UV absorber(s) or the like), stabilize^ s), and the like, and any combination thereof) and / or the thermal additive(s) is / are chosen from thermal initiator(s), photoabsorbers (such as, forexample, UV absorber(s) or the like), stabilizer(s), and the like, and any combination thereof).Statement 14. A composition according to any of Statements 9 to 13, where the photoadditive(s) and / or thermal additive(s) is / are present (e.g., individually or in the aggregate) at about 0.01 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s) or the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.005 to about 2 wt.%, about 33 wt.%).Statement 15. A composition according to any of Statements 9 to 14, where one or more or all of the diluent(s) is / are chosen from reactive diluents (such as, for example, divinyl triethylene glycol, trimethylolpropane diallyl ether, limonene, propargyl alcohol, structural analogs thereof, or any liquid with one or more thiol -reactive unsaturated bonds, and the like, and any combination thereof) and diluents (such as, for example, propylene carbonate, ethylene glycol, dimethyl sulfoxide, ethyl acetate, acetone, structural analogs thereof, and the like, and any combination thereof.Statement 16. A composition according to any of Statements 9 to 12, where the diluent / diluents is / are present (e.g., in the aggregate) at about 1 to about 20 wt.% (relative to the total weight of the composition), including all 0.1 wt.% values and ranges therebetween (e.g., about 0.005 to about 0.01 wt.%, about 0.05%, or less than 0.05 wt.%).Statement 17. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like comprising: irradiating (e.g., with electromagnetic radiation, such as, for example, UV radiation (which may comprise one or more wavelength(s) from about 100 nanometers (nm) to about 450 nm, including all 0.1 nm wavelength values and ranges therebetween)) at least a portion (e.g., a desired portion) or all of a monolith or thermally treating a monolith comprising one or more composition(s) of the present disclosure (such as, for example, composition(s) of any one of Statements 8 to 16), where a plurality of crosslinking groups (e.g., thioether groups or the like) are formed in the at least a portion or all of the at least a portion (e.g., a desired portion) or all of the monolith comprising the one or more composition(s) of the present disclosure macromer(s) and the object, the article of manufacture, or the like is formed; and optionally, one or more postirradiation or post-thermal treatment process(es) (e.g., as described herein).Statement 18. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to Statement 17, where from about 10% to about 100%, including all 0.1% values and ranges therebetween) of the norbomenyl groups are photoreacted or thermally reacted to form the plurality of crosslinking groups.Statement 19. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to Statement 17 or 18, where the monolith is a film or the like and the method further comprises forming the film or the like from (or comprising) the composition(s).Statement 20. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to any of Statements 17 to 19, where the film or the like is formed prior to and / or during the irradiating with electromagnetic radiation of or thermally treating the composition(s).Statement 21. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to any of Statements 17 to 20, where the method is an additive manufacturing method or the like.Statement 22. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to any of Statements 17 to 21, where the additive manufacturing method is a 3-D printing method or the like.Statement 23. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to any of Statements 17 to 22, where the 3-D printing method is digital light processing (DLP), stereolithography (SLA), volumetric printing, UV inkjet printing, two-photon polymerization printing, or the like.Statement 24. A method of forming an object (e.g., a three-dimensional printed object or the like), an article of manufacture, or the like according to any of Statements 17 to 23, further comprising functionalizing the object, the article of manufacture, or the like.Statement 25. An object or an article of manufacture comprising one or more at least partially, substantially, or completely crosslinked macromer(s) (e.g., functionalized macromer(s) or norbornene-functionalized macromer (s)) of the present disclosure or one or more macromer(s) (e.g., functionalized macromer (s) or norbornene-functionalized macromer (s) according to any one of Statements 1 to 6) and / or one or more macromer(s) made by a method of the present disclosure (e.g., macromer(s) made by a method of Statement 7). Statement 26. An object or an article of manufacture according to Statement 26, where the article of manufacture is an object (e.g., a three-dimensional object or the like) or the like and / or comprises one or more three-dimensional feature(s) or the like.Statement 27. An object or an article of manufacture according to Statement 25 or Statement 26, where the article of manufacture is a porous scaffold, at least a part or portion of a surgical prosthesis, at least a part or portion of a wearable electronic object or device, at leasta part or portion of an earbud insert (which may be a custom earbud insert), or at least a part or portion of a microfluidic device, or the like.Statement 28. An object or an article of manufacture according to any one of Statements 25 to 27, where the object or the article of manufacture is porous (e.g., porous as described herein).Statement 29. An object or an article of manufacture according to any one of Statements 25 to 28, where the object or the article of manufacture is comprises an interpenetrating network (e.g. as described herein) (such as, for example, comprising a first network comprising the one or more at least partially, substantially, or completely crosslinked macromer(s) and a second network comprising one or more at least partially, substantially, or completely crosslinked polymer(s), where the first network and the second network are interpenetrating networks).

[0117] The steps of the methods described in the various examples disclosed herein are sufficient to produce one or more macromer(s) or object(s) or article(s) of manufacture or carry out a method of the present disclosure. Thus, in various examples, a method consists essentially of a combination of the steps of the methods disclosed herein. In various other examples, a method consists of such steps.

[0118] The following Examples are presented to illustrate the present disclosure. The Examples are not intended to be limiting in any manner.EXAMPLE 1

[0119] This example provides a description of macromers and compositions and methods of making and using macromers, and uses of macromers and compositions of the present disclosure.

[0120] Norbornene Dicarboximide: A Green Alternative for Thiol -Norbornene Photopolymers (Macromers). Carbic anhydride is an underappreciated starting material for 3D-printable, non-hydrogel photopolymers. Compared with other norbornene precursors, carbic anhydride is cheaper and reactive via aminolysis. As a result, the generalized and efficient functionalization with carbic anhydride can increase the utilization of thiol- norbomene photopolymers. Here, carbic anhydride’s catalyst-free condensation with two commodity polymers: amine-functionalized polypropylene glycol and polydimethylsiloxane is described. The reaction completes in 1 h, produces water as the only byproduct, and does not require purification. It is therefore affordable, facile, and green. Mixing the product with thiol cross-linkers and the appropriate photo-additives produces photopolymers that areprintable via Digital Light Processing. The photopolymers exhibit tunable tensile properties and a functional surface by varying the polymer backbone and thiol stoichiometry. Moreover, the photopolymers are 3D-printed into true-to-scale human aorta models and porous scaffolds with high resolution. The simple yet versatile platform will benefit additive manufacturing of soft materials and beyond.

[0121] The norbornene dicarboximide-functionalized polymers are synthesized from amine-functionalized PPG and PDMS (Scheme 1). Toluene removes the water azeotropically and affords a homogeneous reaction mixture. Regardless of the molecular weight or the amine’s steric hindrance, all reactions proceed to -100% conversion within 1 h (h = hour(s)), as verified by water collected in a Dean-Stark trap.1H-NMR indicates the clean formation of norbomene dicarboximide from the singlet at 6.0-6.1 ppm (FIG. 1). Except for 7kPDMS- 5CA, all products are transparent liquids. 7kPDMS-5CA’s opacity potentially arises from the partial crystallinity of the pendant norbornene dicarboximide propyl side chains. Overall, this green, catalyst-free, and efficient synthesis uses recyclable toluene, produces water, and does not require any purification, thus reducing the cost and difficulty of norbornene functionalization.

[0122] Scheme 1 : Synthesis of norbomene dicarboximide polymers from amine- functionalized polypropylene glycol (PPG) or polydimethylsiloxane (PDMS). The prefix Mnrepresents the average molecular weight of the amine-functionalized starting material. The number preceding CA represents the number of norbornene dicarboximide groups in a single chain. For example, amine-terminated PPG (Mn= 2 kDa) affords 2kPPG-2CA.

[0123] Two thiol cross-linkers, pentaerythritol tetrakis(3 -mercaptopropionate) (PETMP) and 4-6% (mercaptopropyl)methylsiloxane]-dimethylsiloxane copolymer (polySH), are used to study photopolymerization. PETMP is miscible with PPG-based polymers but not with PDMS-based polymers. As a result, 0.9kPDMS-2CA:PETMP is a milky -white mixture. Solubilization of PDMS-based polymers with polySH, which has an Mnof 6-8 kDa and five mercaptopropyl groups per chain on average, was attempted. However, only 5kPDMS- 2CA:polySH is transparent. All immiscible mixtures remain stable emulsions after overnight storage without agitation. 0.9kPDMS-2CA:polySH forms stable, micellar aggregates via an unfavorable interaction between the nonpolar PDMS backbone and the polar PETMP. The relatively polar norbomene dicarboxamide is probably at the exterior to react with PETMP. The immiscibility of 7kPDMS-5CA:polySH is more challenging to explain because 7kPDMS-5CA begins as a milky-white liquid. Favorable interactions between norbomene dicarboximide and mercaptopropyl side chains should still occur. Regardless, aggregate formation may lead to a heterogeneous network and affect the mechanical properties of 3D- printed materials.

[0124] To assess the printability of norbornene dicarboximide photopolymers, their photorheology with 400-500 nm light to capture the common 405 nm wavelength used in many resin printers was investigated. Judging by the cross-over point of loss modulus and storage modulus, only 5kPPG-3CA:PETMP cross-links too slowly (FIG. 6) for DLP printing (385 nm or 405 nm). Cross-linked 5kPPG-3CA:PETMP is also extremely soft and tacky,indicative of a weak network not suitable for DLP 3D-printing. It was initially suspected the partial norbornene functionalization would lead to inefficient cross-linking. However, diffusion NMR of 5kPPG-3CA confirms all norbornenes are covalently linked to the PPG backbone (FIG. 7). Therefore, 5kPPG-3CA:PETMP’s weak mechanical properties may arise from its imperfect network structures (i.e. macrocycles that do not increase the cross-linking density). All other photopolymers cross-link quickly, with various cross-over points (FIG. 2, FIG. 6) reflecting the structure-property relationships. 7kPDMS-5CA:polySH cross-links much faster than 5kPDMS-2CA:polySH because the former has a higher norbomene concentration. Given these results, the heterogeneity of 0.9kPDMS-2CA:PETMP, 7kPDMS- 5CA:polySH, and 5kPDMS-2CA:polySH does not jeopardize the photo-cross-linking. Lastly, the complex viscosity of all formulations is well below 5 Pa s (FIG. 2), which is the upper viscosity limit of commercial DLP printers. 2kPPG-2CA:PETMP is the most viscous due to PPG’s higher crystallinity than PDMS. Among the PDMS-based photopolymers, 7kPDMS- 5CA:polySH is the most viscous due to its PDMS backbone having a higher molecular weight.

[0125] After rheological studies identified four printable formulations (Table 1), 3D- printed dog-bone-shaped specimens were prepared to study their mechanical properties (FIG. 3(A), Table 1), as well as two challenging structures, true-to-scale human aorta and porous scaffolds (FIG. 3 (B)-(D)), to showcase their printability on a commercial DLP printer. Of note, the photopolymers composed of PDMS(7kPDMS-5CA:polySH and 5kPDMS- 2CA:polySH) do not display Tgin the DSC temperature range (-80 - 120 °C). This result agrees with the extremely low Tg, -120 °C, of commercial PDMS elastomers. Switching the thiol cross-linker to PETMP increases the Tgto -8 °C, as observed for 0.9kPDMS- 2CA:PETMP (Table 1). The higher Tgreflects a higher cross-linking density, which is the result of PETMP having a lower molecular weight and a shorter PDMS backbone. Compared with 0.9kPDMS-2CA:PETMP, 2kPPG-2CA:PETMP has a much lower Tg(-49 °C, Table 1) because of its longer backbone and lower cross-linking density. Low Tgensures soft elasticity at room temperature. The absence of melting and crystallization corresponds with the thermal properties of the PPG and PDMS backbones and reflects the limited chain mobility of crosslinked networks.

[0126] Table 1. Properties of various photopolymers.PhotopolymeraE (MPa)csmaxcGmax (MPa)c7g(°C)d2kPPG-2C A:PETMP 3.0 ± 0.1 57% ± 4% 1.1 ± 0.1 -490.9kPDMS-2CA:PETMPb2.1 ± 0.1 97% ± 2% 1.5 ± 0.1 -87kPDMS-5CA:polySH 0.6 ± 0.07 45% ± 1% 0.2 ± 0.07 N / Ae5kPDMS-2CA:polySHb0.08 ± 0.006 82% ± 1% 0.03 ± 0.001 N / AeaAll photopolymers are 3D printable. bOpaque photopolymers with a milky -white color. cDerived from uniaxial tensile testing (n=3). E Yonug’s modulus, £maX: strain-at-failure, Gmax: ultimate tensile strength. dMeasured via differential scanning calorimetry (DSC) on the second heating ramp. eNot detected in the DSC temperature range (-80 °C - 120 °C).

[0127] Next, the effect of the average molecular weight between each cross-linking point(Mc) on the tensile properties was investigated. The 1 : 1 reactivity of thiol -norb omene generates evenly spaced cross-links. Therefore, for 2kPPG-2CA:PETMP and 0.9kPDMS- 2CA:PETMP, Mnof their polymer precursors approximates the Mc. For 7kPDMS- 5CA:polySH and 5kPDMS-2CA:polySH, Mcis inferred by the assumed even distribution of mercaptopropyl groups along the polySH backbone. Uniaxial tensile testing reveals a general trend among the PDMS-based photopolymers: Young’s modulus and ultimate tensile strength inversely correlate with the Mc(Table 1, FIG. 3(A)). The low molecular weight of PETMP, its tetra functionality, and the 0.9-kDa PDMS backbone culminate in the high Young’s modulus (E = 2.1 ± 0.1 MPa) and high tensile strength (<jmax = 1.5 ± 0.1 MPa) of 0.9kPDMS- 2CA:PETMP. Switching the backbone to PPG (Mn= 2 kDa) yields a stiffer network despite a higher Mc, as observed for 2kPPG-2CA:PETMP (Table 1, E = 3.0 ± 0.1 MPa). PPG’s high crystallinity might have contributed to its improved stiffness.

[0128] To demonstrate the printability of our system, porous gyroid pucks (FIG. 3(B)) and a porous gyroid tubular scaffold with 2kPPG-2CA:PETMP and 0.9kPDMS-2CA:PETMP were first printed. Scanning electron microscopy (SEM) shows well-resolved pore structures (FIG. 3B), matching the overall shape of the STL model. Then, true-to-scale human aortas with the two softest elastomers, 5kPDMS-2CA:polySH and 7kPDMS-5CA:polySH, were printed. The aorta model was selected for two reasons. First, it is important in medical education, surgical planning, etc. In addition, the hollow structure has thin walls (< 1 mm) and overhangs; features that are challenging to achieve with 3D-printing. 7kPDMS-5CA:PETMP withstands the suction force generated by the hollow structure upon elevation from the bottom of the resin vat. The well-resolved local features, arch, and arterial branches indicate excellent printability (FIG. 3(C)-(D), FIG. 8). 0.9kPDMS-2CA:PETMP and 2kPPG- 2CA:PETMP, however, adhere more to the fluorinated ethylene propylene (FEP) film of the resin vat and cannot print the thin-walled model. Increasing the wall thickness to 2 mm solves this problem by reinforcing the model (FIG. 9). For 5kPDMS-2CA which has the lowest Young’s modulus (E = 0.08 ± 0.006 MPa), a 2-mm wall is necessary to stabilize the ultra-soft model during printing.

[0129] Compared with acrylate photopolymers, the off-stoichiometric effect is a major advantage of the thiol -norb omene system. The thiol cross-linker as the limiting reagent results in a softer network and a functional surface furnishing unreacted norbomenes. Using 0.9kPDMS-2CA as the model, 0.7 eq of PETMP were added to form the off-stoichiometric photopolymer, which remains printable but has lower tensile properties (E = 0.36 ± 0.04 MPa, £max = 66% ± 2%, Gmax = 0.20 ± 0.02 MPa). A lower glass transition temperature (Zg = - 37 °C) confirms the lower cross-linking density. Detecting unreacted norbornenes using Fourier-Transform Infrared Spectroscopy (FT-IR) fails, as the C=C stretch of norbomene is eclipsed by the carbonyl C=O stretch of PETMP (FIG. 10). Therefore, unreacted norbomenes were converted to amines by grafting cysteamine via thiol -norb omene click chemistry. 3D- printed pucks were exposed to a methanolic cysteamine solution containing 1 wt % TPO at room temperature with or without UV light for 1 h. After thoroughly washing the pucks with ethanol, they were placed in a ninhydrin solution. The sensitive ninhydrin assay detects the resultant free amines by forming a purple imine product colloquially known as Ruhemann’s purple. As thiol -norb omene click chemistry cannot proceed via base catalysis or without radicals, pucks without UV exposure serve as negative controls. Pucks exposed to UV start turning purple within 30 s and become dark purple within a few minutes. Negative controls do not display color changes in the same timeframe. This drastic difference proves the feasibility of surface modification of off-stoichiometric thiol-ene photopolymers.

[0130] Next, norbornene dicarboximide photopolymers were compared with literature precedents. To our knowledge, PPG-based thiol-ene photopolymers have never been reported before. As expected, PPG diacrylate (Mn= 0.4-2 kDa) cross-links into stiff (E = 263-3366 MPa), brittle (smax = 2-12%) materials that require 5-30 vol % PPG (Mn= 0.4 kDa) diluent to be printable via DLP. 2kPPG-2CA:PETMP is therefore more advantageous for soft elastomer applications. The mechanical properties of photopolymers based on 2kPPG-2CA can be further tuned via thiol stoichiometry and the length of the PPG backbone.

[0131] In contrast, PDMS-based thiol-ene photopolymers have applications in soft robotics and microfluidics. The appeal lies in 3D-printing’s efficiency and versatility, which soft lithography hardly possesses. Vinyl- and methacrylate-functionalized PDMS are commercially available and mixing them with thiol cross-linkers like polySH affords 3D- printable photopolymers. However, norbornene functionalization is more advantageous due to its green synthesis presented thus far and documented use in biorthogonal click chemistry. As a result, whether norbomene dicarboxamide-functionalized PDMS exhibits the same mechanical performance was examined.

[0132] The catalyst-free condensation between amine-functionalized PPG or PDMS and CA affords a family of norbornene dicarboximide functionalized polymers — with water as the only byproduct. The reaction is affordable and green and occurs at a 100-g scale without purification. The product constitutes a novel platform for thiol-norbomene photopolymers — which have tunable Young’s modulus, excellent printability on a commercial DLP printer, and a surface for click chemistry modification. Because the molecular weight of amine starting materials ranges from 0.8 to 7 kDa, it was expected that the method would be compatible with commodity small-molecule amines and other high-molecular-weight, amine- functionalized polymers. The broad substrate scope affords a highly rigid or ultra-soft thiolnorbornene network, or anywhere in between. Cheap but versatile, our method can benefit additive manufacturing of soft materials and beyond.

[0133] Materials and Methods. All chemicals were purchased from Sigma Aldrich and Oakwood Chemical and used without purification unless noted otherwise. Diamine terminated and triamine terminated polypropylene glycol are from Scientific Polymer Product Inc. They are also known as Jeffamine® D-2000 and Jeffamine® T-5000, respectively. Amine functionalized polydimethylsiloxane is from Gelest, Inc. NMR spectra were recorded on a Bruker AV III HD 500 MHz spectrometer with a broadband Prodigy cryoprobe or Varian INOVA 400 MHz spectrometer. CDCh was used as the NMR solvent. Differential Scanning Calorimetry (DSC) was conducted on a TA Instruments QI 000 Modulated Differential Scanning Calorimeter to determine glass transition temperature (Zg). Fourier Transform Infrared spectroscopy (FT-IR) was performed on a Bruker Vertex V80V Vacuum FTIR system.

[0134] Synthesis of norbomene dicarboximide functionalized macromers. To a round bottom flask were added 100 g of polymers, carbic anhydride that was equivalent to the amount of amine functionalities, and 50 mL of toluene. A Dean-Stark apparatus and a refluxcondenser were then attached, and the reaction was refluxed for an hour. After cooling to room temperature, toluene was removed in vacuuo to afford the product without purification.

[0135] Formulating photopolymer and 3D printing. The macromers were mixed with the appropriate amount of thiol cross-linkers in a beaker. Next, 0.02 wt.% (relative to macromer + thiol weight) of 2,5-bis(5-tert-butyl-benzoxazol-2-yl)thiophene (BBOT), 0.6 wt.% of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), and

[0136] 0.02 wt % of (2,2,6,6-tetramethylpiperidin-l-yl)oxyl (TEMPO) were dissolved in a small amount of acetone and added to the mixture. For off-stoichiometric photopolymer (e.g. norbornene is in excess relative to thiol), 0.7 equivalent of pentaerythritol tetrakis(3- mercaptopropionate) (PETMP) was added. Resultant photopolymers were stored away from light and poured into the photopolymer vat for 3D printing (Asiga Max). Specifically, STL files were sliced with Asiga Composer, with a base layer exposure for 6 s at 30 mW / cm2, and all subsequent layers at 20 mW / cm2for 2-3 s. The prints were post-processed by washing briefly in ethyl acetate and cured under ultraviolet radiation (Asiga Flash UV Chamber) for one hour. All prints were dried in vacuuo on a Schlenk line for 24 h at room temperature before any characterization.

[0137] Photopolymer characterization. Macromers were characterized viaJH NMR (FIG. 4 and 5) and FT-IR. Complex viscosity was measured on a TA Instruments DHR3 Rheometer. Specifically, photopolymer samples were subjected to an oscillatory frequency sweep (angular frequency 0.1-500 rad / s, oscillation strain: 10%) between two parallel plates at 25 °C. Cured photopolymer properties were characterized with FT-IR, DSC, and uniaxial tensile testing, all according to our previous protocol. Photorheology was conducted at room temperature on a TA Instruments DHR3 Rheometer equipped with a UV curing accessory (400 - 500 nm filter); the geometry was a 20 mm parallel plate, composed of a disposable aluminum upper plate and an acrylic lower plate. A 400-5000 nm UV filter was used, and the power output was 10 mW / cm2.

[0138] Aorta 3D Model Generation. Anonymized patient CT angiography DICOM data was segmented and converted to a 3D model using STL language.

[0139] Ninhydrin Assay. Circular pucks with 6 mm diameter and 1 mm height were 3D printed according to the protocol above. In dram vials, each puck was immersed in cysteamine solution in ethanol containing 1 wt % of TPO. The vials were either exposed to UV or left in the dark for an hour. Afterward, each puck was taken out, washed thoroughly in ethanol, immersed in ninhydrin solution for five minutes, and finally washed again with ethanol.EXAMPLE 2

[0140] This example provides a description of macromers and compositions and methods of making and using macromers, and uses of macromers and compositions of the present disclosure.

[0141] Caffeine-catalyzed synthesis of photopolymers (macromers). An elastomeric and degradable thiol -norb omene photopolymer with good biocompatibility will revolutionize 3D printing for biomedical applications. Here, a caffeine-catalyzed in-tandem ring-opening reaction of cis-5-norbomene-endo-2,3-dicarboxylic anhydride and propylene oxide by alcohol-terminated polycaprolactone at a 90-g scale is described. The synthesis is purification-free, moisture-tolerant, and adheres to green chemistry principles. Mixing the products with thiol cross-linkers and photo-additives affords the thiol -norb omene photopolymer resin. Digital Light Processing converts the resin into high-fidelity prints with excellent elastic recovery. Printed objects include a 3D aortic arch and branched carotid artery rendered from anonymized patient CT scans and microfluidic devices with patent 3D corkscrew channels. Caffeine-catalysis affords various percentages of alcohol chain end that controls the photopolymer’s degradation rate. The material demonstrates good biocompatibility in vitro and in a subcutaneous implantation model. The elasticity, biocompatibility, affordability, sustainability, and versatility of this new photopolymer platform will open up new opportunities for 3D printing in biomedical applications and beyond.

[0142] The design considered two factors. First, biocompatible photochemistry. Scalable photopolymers commonly use (meth)acrylates whose free radical cross-linking is inhibited by oxygen. This leads to unreacted monomers that jeopardize biocompatibility. Thus, thiol - norbomene click chemistry was chosen for its high conversion, insensitivity to oxygen, uniform cross-linked networks, and superior biocompatibility.

[0143] Second, the starting material and its norbornene functionalization was considered. Polycaprolactone-based materials have excellent biocompatibility and resorbability. Furthermore, alcohol-terminated polycaprolactone (PCL) is a commodity chemical that will lower the cost of photopolymers. For the functionalization of PCL, cis-5-norbomene-endo- 2,3-dicarboxylic anhydride (CA) — synthesized from maleic anhydride — is cheaper and greener than other norbornene precursors. Caffeine catalysis was used to enable the intandem ring opening of CA and propylene oxide (PO) by alcohol-terminated PCL at a 90-g scale (limited by reaction vessel size). Mixing the product — without purification — withpentaerythritol tetrakis(3 -mercaptopropionate) (PETMP) and appropriate photo-additives affords thiol-norbornene photopolymers. DLP transforms the photopolymers into tough, elastomeric structures with tunable mechanical properties, controlled degradability, promising biocompatibility, and customized shapes including patient-specific geometries. |0144] Scheme 2: Synthesis of norbomene-functionalized polycaprolactone (PCL). PCL diol (bPCL) and PCL triol (tPCL) can be used, and the products are abbreviated accordingly. For the caffeine-catalyzed in tandem ring opening (CITRO) of CA and PO, the numerical suffix represents the percentage of the alcohol chain ends.Fast Slow

[0145] Results and Discussion. Synthesis and chain-end control. Ring-opening CA affords carboxylic acid chain ends Scheme 2. Eliminating them was expected to achieve controlled degradation which is desirable in many material applications. Therefore, theinstant synthesis used caffeine-catalyzed in tandem ring opening (CITRO) of CA and PO initiated by alcohol -terminated PCL Scheme 2. 1 mol% of caffeine catalyzes the quantitative conversion of terminal carboxylic acids to alcohols after 44 h Scheme 2. Decreasing the reaction time to 17 h lowers the percentage of alcohol chain ends to 41%, yielding tPCL-CA- PO41 (FIG. 11). Unlike the caffeine-free synthesis (FIG. 11, FIG. 18), CITRO reaches 100% CA conversion. This can be due to the extended reaction time, the catalytic effect of caffeine, or a combination of both. Elimination of the acid chain end via H2SO4- or lipase-catalyzed esterification with ethanol or hexanol was tried. However, the result was extensive transesterification of the PCL backbone that renders the final product unable to cross-link. CITRO avoids this due to the absence of excess alcohol. Caffeine was used to catalyze the transformation. This likely also promotes the ring opening of CA by alcohol in CITRO, evident by the 100% CA conversion of CITRO.

[0146] Besides chain-end functionality, CITRO is well-controlled in two more aspects. First, environmental moisture does not initiate the reaction, as indicated by the unimodal distribution of resonances on diffusion NMR (FIG. 19). The GPC traces of tPCL-CA-POlOO (FIG. 11) and tPCL-CA-PO41 FIG. 20) suggest the same result via their unimodal molecular weight distributions. Second, excess PO does not form ether linkages that sometimes occur under base catalysis:JH-JH correlated NMR spectroscopy (COSY) indicates no methyl CH3 and methylene (CH2) coupling in the ether region (5 = 3.75-3.5 ppm, (FIG. 11). A peak at ~5.0 ppm was noticed (FIG. 21 and 22)), corresponding to the methine (CH) proton adjacent to an ester bond. Its correlation to the methyl CH 3) group at 1.13 ppm suggest that a minor fraction of PO is ring-opened at the methine group (FIG. 11). bPCL-CA-POlOO and tPCL- CA-PO100 respectively contain 36% and 21% of this minor regioisomer (FIG. 21 and 22). Expectedly, the regioselectivity favors COOH attacking PO on the less-hindered methylene group. CITRO’ s regioselectivity is comparable to that of ring-opening of PO by acetic acid catalyzed by a salenCo(III) complex. Unlike metal salen complexes, caffeine does not have known asymmetric catalytic activity. Regardless, it is not believed the regioselectivity would affect the properties of the final materials.

[0147] Overall, CITRO is a simple, green platform for accessing PCL-based norbornene macromers with tunable chain-end functionality. The catalyst, caffeine, is generally regarded as safe (GRAS) by the FDA, therefore eliminating laborious purification and hazardous waste. The moisture-tolerant mechanism requires only a simple benchtop setup. The only toxic starting material is PO but easily removed.

[0148] In terms of norbomene functionalization of primary alcohols, CITRO is greener and easier. Previous methods include carbodiimide-mediated esterification of 5-norbomene- 2-carboxylic acid, ring opening of CA catalyzed by 4-dimethylaminopyridine (DMAP), and ring-opening (co)polymerization of norbomene carbonate or CA. These methods can present various obstacles to scale-up. Carbodiimide yields a stoichiometric amount of urea byproduct; thus, it has low atomic efficiency and necessitates laborious purification. On the other hand, ring-opening reactions — whether mono-functionalization or (co)polymerization — have high atomic efficiencies but can suffer from the potential toxicity of residual catalysts. DMAP used in base-catalyzed ring-opening of CA and the transition metal catalyst used in ROCOP are two examples. These deficiencies lead to poor atomic efficiency, laborious purification, and a high price tag.

[0149] High-fidelity DLP 3D printing. Adding a stoichiometric amount of PETMP and appropriate photo additives (FIG. 12(A)) to each macromer affords the corresponding thiol - norbomene photopolymer. One main benefit of thiol -norbomene photopolymers is their homogenous network (FIG. 12(B)), whose cross-linking is not susceptible to oxygen inhibition. First, 3D-printed porous gyroid tubular structures show desirable pore (200-300 pm diameter) and stmt resolution (FIG. 13(A)), suggesting high fidelity to CAD models. These porous structures are useful as scaffolds to culture cells.

[0150] 3D-printing microfluidic devices is another application of photopolymers (FIG. 23). Enclosed channels are challenging to 3D print because UV penetration can cure leftover resins in the enclosed channel. Although this renders the maximum resolution of DLP much lower than that of soft lithography, DLP can fabricate true 3D devices, like the one with corkscrew-shaped channels (1 mm diameter, (FIG. 23). Such geometries would have been laborious and costly, if practical, to fabricate through soft lithography. As the channel narrows to 500 pm and 250 pm, the uncured photopolymer becomes harder to clear during printing, as evidenced by the partially clogged 500 pm channels and fully clogged 250 pm channels (FIG. 23). With the refinement of the photoabsorber and photoinitiator concentrations and investment in a printer optimized for microfluidic printing, it is expected that these materials can produce microfluidic devices with narrower channels.

[0151] 3D-printed personalized, resorbable surgical prostheses are another high-impact application. Conventional fabrication methods (extrusion, textile, electrospinning, etc.) do not meet the demand for precision and personal medicine at scale. Take human arteries: the dominant Dacron™ and expanded polytetrafluoroethylene (ePTFE) grafts are orders of magnitude stiffer than native arteries. This compliance mismatch causes poor patientoutcomes. 3D-printable, biodegradable elastomers enable 3D printing of personalized vascular grafts. Aanonymized patient CT angiography DICOM data was segmented and converted to 3D models using STL language. The aortic arch was printed at 50% scale to fit the maximum build volume with a 1.5 mm effective wall thickness. The common carotid artery was printed true-to-size but with a 2 mm wall thickness because the DLP printer used is not optimized for low-adhesion-force printing necessary for soft materials. Even the softest material, 0.7-bPCL-CA (Table 2), can print challenging hollow artery models, although its low strength makes it more prone to failure. Nevertheless, both prototypes match their respective 3D models with clearly defined details and patent, flexible arterial branches (FIG. 13(B)), (FIG. 24)).

[0152] Mechanical properties of CA-functionalized photopolymers. The instant photopolymers' low glass transition temperature (Tg) reflects their amorphous nature at room temperature and above (Table 2). All networks withstand 100 cycles of loading and unloading between 0-25% strain without plastic deformation (FIG. 14(A)-(D)). This strain range is relevant to tissue engineering because many mechanically active tissues such as ligaments and arteries typically experience less than 20% strain under physiological conditions. Nevertheless, none of our photopolymers exhibit melting or crystallization points. The PCL backbone is likely too small to significantly contribute to the thermal properties of networks, but different backbone structures (bPCL or tPCL) result in disparate mechanical properties. Overall, tPCL-based networks (tPCL-CA-POlOO: E = 3.4±0.1 MPa, tPCL-CA- PO41 : E = 3. l±0.1 MPa) are stiffer than the bPCL-based networks (bPCL-CA-POlOO: E = 2.8±0.1 MPa, bPCL-CA: E = 2.4±0.03 MPa). Because only two out of the three alcohols in tPCL are functionalized, the third alcohol likely hydrogen-bonds with one another and increases Young’s modulus. Another contributing factor is the higher crystallinity of tPCL due to its higher molecular weight.

[0153] Table 2. Network properties.Network E (MPa)ccmax Cmax (MPa)cZg (°c)dbPCI.-C.V 2.4 : 0.03 61% ± 17% i .o : 0.2 bPCL-CA-POlOO 2.8 ± 0.1 43% ± 2% 1.0 ± 0.10.7-bPCL-CAb0.3 ± 0.03 270% ± 29% 0.5 ± 0.1 -10 tPCL-CA-POlOO 3.4 ± 0.1 52% ± 1% 1 3 =1= 0.1 -18 tPCL-CA-PO41 3.1 ± 0.1 56% ± 7% 1.3 ± 0.1 formulated using a stoichiometric amount of PETMP. bOff-stoichiometric (OS) formulation is formulated with 0.7 eq of PETMP. cDerived from stress-strain curves (n = 3). A: Young’s modulus; amaX: strain-at- failure; Cmax : ultimate tensile strength. dMeasured by Differential Scanning Calorimetry (DSC) at the second heating ramp.

[0154] The degree of CA functionalization and thiol stoichiometry also affects the mechanical properties. CITRO leads to complete norbornene functionalization. Compared with bPCL-CA which has 80% functionalization, the CITRO photopolymers have a higher cross-linking density. As a result, the bPCL-CA-POlOO network (E = 2.8±0.1 MPa) is slightly stiffer than the bPCL-CA network (E = 2.4±0.03 MPa). Furthermore, an increasing percentage of alcohol chain ends (tPCL-CA-PO41 vs tPCL-CA-POlOO) have little impact. This is likely because alcohol and carboxylic acid are both capable of hydrogen bonding. Another parameter that can be controlled is the thiol stoichiometry. Adding 0.7 eq of PETMP formulates an off-stoichiometric photopolymer (0.7-bPCL-CA). The 0.7-bPCL-CA (E = 0.30±0.03 MPa) network is softer than its counterparts with stoichiometric amounts of PETMP (Table 2, bPCL-CA). Its 7gcorrespondingly decreases to -10 °C. The lower elastic modulus and Tg, and the increased strain-at-failure are expected, as a lower cross-linker concentration typically lowers the cross-linking density.

[0155] Overall, three factors control the mechanical properties of this series of photopolymers: macromer backbone, degree of CA functionalization, and thiol stoichiometry. The tunable Young’s modulus ranges from ~0.3 MPa to 3.4 MPa — with an off-stoichiometric amount of PETMP resulting in the softest network (0.7-bPCL-CA, E = 0.30±0.03 MPa), while the more crystalline tPCL backbone and 100% CA functionalization, tPCL-CA-POlOO, yields the stiffest network (E = 3.4±0.1 MPa). The low-molecular-weight tPCL (Mn= 0.9 kDa) and bPCL (Mn= 0.5 kDa) used here contrast the higher-molecular- weight bPCL (Mn= 2.3-8.4 kDa) used to synthesize 3D-printable thiol-ene photopolymers in Thijssen et al.,26which are stiffer (E = 66-252 MPa) and have early yield points (a = 10 - 20%) due to PCLcrystallization. Therefore, our photopolymer platform targets applications that require relatively soft and elastic materials. One such area is the tissue engineering of vital organs: the range of Young’s modulus covers tissues such as the heart, lungs, arteries, and veins. Cyclic testing shows these materials’ promise in the dynamic physiological environment.

[0156] Moreover, 0.7-bPCL-CA was directly compared with a state-of-the-art commercial elastic resin, Formlabs BioMed Elastic 50A. Uniaxial tensile testing was performed on a ring-shaped cross-section of the 3D-printed grafts to compare their mechanical properties. The ring test’s stress-strain relationship first warrants test parameter validation. The calculated Young’s modulus from the ring tests agrees with that derived from tensile testing using dog-bone-shaped specimens (Table 2). According to cyclic stress-strain curves of the ring test, 3D-printed 0.7-bPCL-CA (FIG. 15) has near-identical mechanical stress after 500 cycles of loading and unloading between 0-40% strain, whereas Formlabs BioMed Elastic 50A displays a noticeable energy loss (FIG. 15), indicating plastic deformation. In addition, artery models printed using 0.7-bPCL-CA exhibit a higher circumferential failure strain (FIG. 16). Another difference is Formlabs BioMed Elastic 50A’s pronounced toe region at 0-20% strain (FIG. 15). The MSDS of Formlabs BioMed Elastic 50A states that the resin is made from polyurethane acrylate macromers. The resin is also very viscous. Thus, the polyurethane likely has a larger molecular weight than the PCL macromers used in our resin. Uncoiling of the polyurethane backbone likely contributes to the long toe region.

[0157] Tunable degradability via macromer backbone and chain end functionality. For tissue engineering, tunable and well-controlled degradability is critical. Expectedly, the bPCL-CA network rapidly degrades in 60 mM NaOH at 37 °C (FIG. 25): its specimens lose 50% mass in 4.5 h. They become more brittle and rigid post-degradation, consistent with the trend observed in many other polyesters after hydrolytic degradation. The rapid degradation is consistent with known literature on locally low pH caused by terminal carboxylic acids accelerating hydrolytic degradation.

[0158] Converting the terminal carboxylic acids to alcohols via CITRO slows down the degradation. The bPCL-CA-POlOO network loses 20% mass after 48 h in 0.25 M NaOH solution at 37 °C, and the tPCL-CA-POlOO network loses 60% mass in the same period (Error! Reference source not found.6A). Conversely, preserving a portion of the terminal carboxylic acids accelerates the degradation: the tPCL-CA-PO41 network degrades over 20 times faster than the tPCL-CA-POlOO network (FIG. 16(A)). The observed linear degradation indicates a surface erosion mechanism. SEM images of the tPCL-CA-POlOOnetwork before and after 48 h of degradation support this claim. Except for some microcracks, the surface of the partially degraded specimens appears almost identical to those of the fresh specimens (FIG. 16(A)). Unlike many other surface-eroding polyesters, the instant polyester-based photopolymers lack the characteristic erosion after degradation. This may be due to the layer-by-layer profile of the DLP-printed specimens. Lastly, between tPCL-CA- POIOO and bPCL-CA-POlOO, tPCL causes the network to degrade twice as fast, likely because of the plasticizing effect of the unfunctionalized PCL arm. Combined, CITRO affords clickable photopolymers with a controllable and wide range of degradation rates.

[0159] In addition to linear mass loss, surface erosion prevents a sudden loss of material strength during degradation. The mechanical properties of the tPCL-CA-POlOO and bPCL- CA-POIOO were investigate networks at different stages of degradation. Instead of a decrease in stiffness, as observed for other surface-eroding elastomers such as poly(glycerol sebacate), mechanical properties of the tPCL-CA-POlOO and bPCL-CA-POlOO networks either remain unchanged or increased (FIG. 16(B)), FIG. 26). This trend also holds in the faster-degrading tPCL-CA-PO41 network (FIG. 16(C)), suggesting the beneficial effect of maintaining mechanical integrity by even partially capping the terminal carboxylic acids. The preservation of mechanical properties further supports a controlled surface erosion mechanism during which a slight decrease in the cross-linking density increases the chain length between cross-links. This does not significantly affect Young’s modulus but disproportionately increases the strain-at-failure.

[0160] Biocompatibility. The cytocompatibility of our photopolymers is assessed with bPCL-CA and tPCL-CA-POlOO networks. Direct seeding of human umbilical vein endothelial cells (HUVECs) on test surfaces was chosen as a representative of possible cellular responses to a print. Compared with tissue-culture-treated polystyrene (TCPS), the bPCL-CA and the tPCL-CA-POlOO networks are both cytocompatible (FIG. 17(A)), as >75% viability indicates cytocompatibility per the ISO 10993-5 standard. Furthermore, Calcein-AM staining on Day 1-4 shows identical cell morphologies on all surfaces (FIG. 17(B), FIG. 27). Further, the growth curve indicates that HUVECs proliferate at roughly the same rate on all test surfaces (FIG. 28). As a result, bPCL-CA’ s terminal carboxylic acids do not impact the viability and cell morphology (FIG. 17(B)).

[0161] Encouraged by this result, a preliminary subcutaneous implant study of the tPCL- CA-PO100 network using 3D-printed porous pucks (FIG. 17(C)) was conducted. Two female BALB / cJ mice each received two implants that were explanted after 15 days (FIG. 17(C)). The absence of foreign body giant cells, preservation of the muscle layer’s nativearchitecture, and vascularized surrounding tissues represent a benign response to an implant. Interestingly, the host develops a vascularized cellular infiltration into the pores of the print. The vascularized nature of the host response and the relatively thin capsule during the early phase are encouraging signs of biocompatibility. Further studies will explore inflammatory cells' nature and potential phenotype changes over longer periods.

[0162] Comparison with other sustainable photopolymers. CITRO is a step toward sustainable 3D printing material. In this platform, CA is partially renewable as it is synthesized from maleic anhydride, and PCL is a well-established renewable polymer. This Example takes thiol-ene photochemistry further in applications, such as, for example, biomedical research and application in medicine.

[0163] Caffeine catalyzes the green synthesis of PCL-based thiol -norb omene photopolymers for 3D printing. Varying the reaction time tunes the chain-end functionality, which in turn controls the degradation kinetics of the final thiol -norb omene photopolymers. The photopolymers also exhibit mechanical properties that vary with the backbone structure and thiol stoichiometry. These photopolymers are highly elastic when repeatedly extended to 40% strain. Lastly, in vitro study with human umbilical vein endothelial cells shows high cytocompatibility and early-phase subcutaneous implantation in mice elicits a benign host response. Thus, this photopolymer platform is poised to enable new applications of additive manufacturing of soft biomaterials and beyond.

[0164] Materials and Methods. All chemicals were purchased from Sigma Aldrich and Oakwood Chemical and used without purification unless noted otherwise. Polycaprolactone diol (bPCL, Mn= 530 g / mol) and polycaprolactone triol (tPCL, Mn= 900 g / mol) were from Placcel Inc. NMR spectra were recorded on a Bruker AV III HD 500 MHz spectrometer with a broadband Prodigy cry oprobe or Varian INOVA 400 MHz spectrometer. CDCh was used as the NMR solvent. Differential Scanning Calorimetry (DSC) was conducted on a TA Instruments QI 000 Modulated Differential Scanning Calorimeter to determine glass transition temperature (7g). Scanning electron microscopy (SEM) was conducted on a Jeol JCM-7000 benchtop SEM.

[0165] All error bars represent the standard error of an n=3 sample size. Statistical significance is determined via Student’s t-test.

[0166] Synthesis of PCL-derived macromer. For uncatalyzed thermal condensation, bPCL and cis-5-norbomene-endo-2,3-dicarboxylic anhydride (CA) (1 :2 molar ratio) were combined in a round bottom flask equipped with a stir bar. The reaction was then stirred at 95 °C for 5 h. The product was a viscous, clear liquid upon cooling to room temperature. Forcaffeine-catalyzed reactions, bPCL or tPCL, CA, and propylene oxide (PO) (molar ratio: 1 :2: 10) were added to a threaded glass pressure flask (Ace Glass). To this mixture was then added 1 mol% (relative to CA) of caffeine. The flask was sealed with a Teflon plug. The reaction was then stirred at 90 °C for the appropriate amount of time, after which excess PO was removed in vacuuo to yield a viscous product.

[0167] Formulating Photopolymer and 3D Printing. Because carboxylic acid end groups on bPCL-CA increased the photopolymer viscosity, 10 wt.% of propylene carbonate was added to formulate bPCL-CA photopolymers, regardless of thiol stoichiometry. Other macromers did not require dilution. Next, 0.05 wt.% of 2,5-bis(5-tert-butyl-benzoxazol-2- yl)thiophene (BBOT), 0.5 wt.% of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), and 0.01 wt.% of (2,2,6,6-Tetramethylpiperidin-l-yl)oxyl (TEMPO) were dissolved in a small amount of acetone and added to the synthesized macromer. To the homogenized mixture was then added an appropriate amount of pentaerythritol tetrakis(3- mercaptopropionate) (PETMP) to reach the desired thiol -to-norbomene ratio. 0.7 equivalent of PETMP was added to yield an off-stoichiometric photopolymer. The resultant photopolymer was stored away from light and poured into the photopolymer vat for Digital Light Processing (DLP) 3D printing (Asiga Max).

[0168] For 3D printing, STL files were sliced with Asiga Composer, with a base layer exposure for 6s at 30 mW / cm2, and all subsequent layers at 3 s for 20 mW / cm2. The prints were post-processed by washing briefly in ethyl acetate and cured under ultraviolet radiation (Asiga Flash UV Chamber) for 1 h. If the photopolymer was diluted with propylene carbonate, the prints were washed in ethanol at room temperature for a day. All prints were then air-dried for three days before any characterization.

[0169] Photopolymer Characterization. Macromers were characterized viaJH NMR. Photopolymer viscosity was measured on the TA Rheometer. Cured photopolymer properties were measured with, DSC and uniaxial tensile testing.

[0170] Aorta 3D Model Generation. Anonymized patient CT angiography DICOM data was segmented and converted to a 3D model using STL language.

[0171] Accelerated Degradation Test. Circular pucks with 6 mm diameter and 1 mm height were 3D printed according to protocol. After drying, pucks were weighed, transferred to dram vials containing 4 mL of 60 mM or 250 mM NaOH, and agitated at 37 °C for a predetermined amount of time. At the end of each time point, the pucks were washed with water, vacuum dried, and weighed to determine percentage weight loss.

[0172] In Vitro Cytocompatibility. To prepare thin films for cytocompatibility study, 6- mm glass coverslips were briefly dipped in 1 wt.% solution PCL (in chloroform) or thiol- norbomene photopolymer (in acetone). After air-drying overnight, the coverslips were incubated under ultraviolet light (Asiga Flash UV Curing Chamber) for thirty minutes. They were then placed in 24-well plates and washed three times with 100% ethanol for twenty minutes per wash. The in vitro cytocompatibility test was performed using Human umbilical vein endothelial cells (HUVEC, C2519A, Lonza, MD). HUVEC (passages 4-6) were cultured using an endothelial cell growth medium MV 2 kit that contained 5% Fetal Bovine Serum and supplements (C-22121, PromoCell / VWR, PA). The cells were harvested using trypsin- EDTA after reaching confluency, neutralized with medium, centrifuged at 200g for 5 minutes, and resuspended to obtain 104cells / mL. 50 pL of the suspension (500 cells / 50 pL) was added dropwise onto the coverslips and the cells were incubated for 3 h before ImL of the medium was added to each well. Cells were incubated at 37 °C with 100% humidity and 5% CO2. The medium was exchanged every 48 h. Cell Titer Gio 2.0 assay kit (G9241, Promega, WI) was used to measure the luminescence of the amount of ATP present, which indicated the presence of metabolically active cells after 1, 2, 3, and 4 days. The luminescence (Relative Light Units (RLU)) was recorded using a SpectraMax M3 microplate reader (Molecular Devices, CA). A Live assay was performed on days 1-4 using Calcein-AM (C3100MP, Invitrogen, NY). Live cells were identified when calcein-AM in medium (IpM final concentration) was converted to green fluorescence after interacting with intracellular esterases. The fluorescent images were observed using a Nikon ECLIPSE Ti fluorescence microscope (Nikon Instruments INC., NY).

[0173] In Vivo Biocompatibility. The study was conducted according to an approved protocol (Cornell University IACUC protocol number: 2017-0118). Ethylene oxide-sterilized tPCL-CA-PO implants (diameter of 6 mm and thickness of 1 mm) were implanted in 2 female BALB / cJ mice (Jackson Laboratory) with an average age of 8-9 weeks. Under deep isoflurane-CL general anesthesia, the samples were implanted subcutaneously in the back of the mice by blunt dissection. After 14 days the animals were sacrificed and tissues (~15 x 15 mm) surrounding the implants were harvested with the intact implants. Tissues were fixed in 4% paraformaldehyde for 1.5 hours and soaked in 30% sucrose for 48 hours and embedded in Shandon™ Cryomatrix™ embedding resin (Thermo Scientific™).

[0174] Serial cross-sections at the center, quarter and edge of each implant (8 pm thick, longitudinal axial cut) were stained with hematoxylin and eosin (H & E) to examine host responses such as inflammation and other adverse effects. All reagents for H & E stainingwere obtained from Electron Microscopy Sciences, PA, USA. All imaging was performed on a Nikon Eclipse Ti2-E inverted microscope, and image analysis was performed with NIS Elements software (Tokyo, Japan).EXAMPLE 3

[0175] This example provides a description of macromers and compositions and methods of making and using macromers, and uses of macromers and compositions of the present disclosure.

[0176] Emulsion Polymerization Formulation and Polymerization of Same. High Internal Phase Emulsion (HIPE) Formulation: Dissolve 20 mL of thiol -norb omene resin was dissolved in 20 mL of toluene. With rapid stirring, about 120 to about 160 mL of water containing 0.25 wt.% of hyaluronic acid was then added, yielding a milky-white emulsified mixture. The mixture can be 3D printed directly with desktop DLP / SLA printer or cured in a glass mold with 405 nm UV light. The afforded photoset is referred to as PolyHIPE.

[0177] PolyHIPE Post-processing. 3D printed or molded PolyHIPE was washed briefly with alcohol, immersed in water, and post-cured with 405 nm light for an hour to reach full mechanical strength. Subsequent freeze-drying afforded porous structures (FIG. 29 and FIG. 30). The resultant material is soft (E = 77 ± 6 kPa).

[0178] Strengthening PolyHIPE with Interpenetrating Network (IPN). The polyHIPE specimens were placed in an ethanolic solution comprising monomers (ethyl acrylate and N- vinylpyrrolidone in a 95:5 ratio), 0.25 vol % of butanediol diacrylate (relative to monomers), and 0.5 wt.% of azobisisobutyronitrile (relative to monomers). Excess monomer was used. The specimens are swollen until equilibrium. Then, they are immersed in a hot glycerol bath (75 to 80°C) with gentle stirring for two hours. This heat treatment crosslinks the secondary poly(acrylate) network, yielding a IPN with the first network comprising the polyHIPE, the second network comprising the poly (acrylate) network.

[0179] The resultant polyHIPE-IPN has improved mechanical properties (E = 137 ± 9 kPa) while retaining porosity (FIG. 31). In the case of porous tubular conduits, such as, for example, porous tubular conduits suitable for rat carotid artery implant or the like, the polyHIPE-IPN has sufficient suture retention force (greater than about 100 mN). In certain cases, a non-porous interior was observed. Lastly, polyHIPE-IPN retains mechanical properties (E = 149 ± 32 kPa) and porosity after steam sterilization (FIG. 31).

[0180] Although the present disclosure has been described with respect to one or more particular examples, it will be understood that other examples of the present disclosure may be made without departing from the scope of the present disclosure.

Claims

CLAIMS:

1. A macromer comprising one or more oligomer group(s), each oligomer group comprising one or more norbornene group(s).

2. The macromer of claim 1, wherein the oligomer group(s) comprise the following structure:OG-(NBG)x, wherein OG is an oligomer group, NBG is a norbornene group, and x is 1 to 20.

3. The macromer of claim 1, wherein each of the oligomer group(s) independently comprises a plurality repeat groups independently chosen from ether repeat units, dimethylsilioxane repeat units, structural analogs thereof, and any combination thereof.

4. The macromer of claim 1, wherein the oligomer group(s) independently comprise: one or more polyhydroxyalkanoate(s), one or more polycaprolactone diol group(s), polylactide group(s), polyglycolide group(s), one or more poly ether group(s), one or more polypropylene glycol group(s), one or more polyethylene group(s); one or more polytetrahydrofuran group(s), one or more polycarbonate group(s), one or more polycarbonate diol group(s), one or more polycarbonate triol group(s), one or more PDMS bisamine group(s), a structural analog thereof, or any combination thereof.

5. The macromer of claim 1, wherein the norbornene group(s) independently comprise the following structure:structural analog thereof, a stereoisomer thereof, or an isotopic variant thereof, wherein L is a linking group or wherein two L groups taken together form a ring.

6. The macromer of claim 1, wherein the oligomer group(s) independently comprise(s) a molecular weight of about 200 g / mol to about 10,000 g / mol.

7. A method of making a macromer or macromers comprising: forming a reaction mixture comprising; one or more oligomer(s), one or more norbornene group precursor(s), optionally, one or more base catalyst(s), and optionally, one or more aliphatic epoxide(s); and holding the reaction mixture, wherein the macromer or macromers is / are formed.

8. The method of making a macromer or macromers of claim 7, wherein the norbomene group precursor(s) is / are chosen from carbic anhydride (CPMA), norbornyl halides, structural analogs thereof, and any combination thereof.

9. The method of making a macromer or macromers of claim 7, wherein the oligomer(s) independently comprise a plurality of ether repeat units, a plurality of dimethylsilioxane repeat units, or a structural analog thereof, or any combination thereof.

10. A composition comprising one or more macromer(s) of claim 1.

11. The composition of claim 10, wherein the macromer(s) is / are present at about 50 to about 99 wt.% (relative to the total weight of the composition).

12. The composition of claim 10, further comprising one or more crosslinker(s);one or more photoadditive(s), wherein at least one of the photoadditive(s) is / are one or more photoinitiator(s) and / or one or more thermal additive(s), wherein at least one of the thermal additives is a thermal initiator; and optionally, one or more diluent(s).

13. The composition of claim 12, wherein the crosslinker(s) is / are chosen from thiols, dithiolanes, structural analogs thereof, and any combination thereof.

14. The composition of claim 12, wherein the crosslinker(s) is / are present at about 5 to about 20 wt.% (relative to the total weight of the composition)).

15. The composition of claim 12, wherein the photoadditive(s) is / are chosen from photoinitiator(s), photo absorber(s), stabilizer(s), and any combination thereof) and / or the thermal additive(s) is / are chosen from thermal initiator(s), thermal absorber(s), stabilizer(s), and any combination thereof.

16. The composition of claim 12, wherein the photoadditive(s) and / or thermal additive(s) is / are present at about 0.01 to about 3 wt.% (relative to the total weight of the macromer(s) and crosslinker(s)).

17. The composition of claim 12, wherein the diluent(s) is / are reactive diluent(s) chosen from divinyl triethylene glycol, trimethylolpropane diallyl ether, limonene, propargyl alcohol, structural analogs thereof, and any combination thereof and / or diluent(s) chosen from propylene carbonate, ethylene glycol, dimethyl sulfoxide, ethyl acetate, acetone, structural analogs thereof, and any combination thereof.

18. The composition of claim 12, wherein the diluent(s) is / are present at about 1 to about 20 wt.% (relative to the total weight of the composition).

19. The composition of claim 10, wherein the composition is an emulsion.

20. The composition of claim 19, further comprising water, optionally, one or more solvent(s) chosen from hydrocarbons, ketones, alkyl benzenes, halogenated analogs thereof,halogenated solvents, structural analogs thereof, and any combination thereof, and one or more thickener(s) and / or one or more emulsifier(s).

21. A method of forming an object or an article of manufacture comprising irradiating with electromagnetic radiation at least a portion or all of a monolith or thermally treating a monolith comprising one or more composition(s) claim 10, wherein a plurality of crosslinking groups is formed in the at least a portion or all of the at least a portion or all of the irradiated monolith or thermally treated monolith comprising the one or more composition(s) and the object or the article of manufacture is formed.

22. The method of forming an object or an article of manufacture of claim 21, wherein about 10% to about 100% of the norbornenyl groups of the macromer(s) of the one or more composition(s) of claim 10 is photoreacted or thermally reacted to form the plurality of crosslinking groups.

23. The method of forming an object or an article of manufacture of claim 21, wherein the monolith is a film and the method further comprises forming the film comprising the composition(s).

24. The method of forming an object or an article of manufacture of claim 23, wherein the film is formed prior to and / or during the irradiating with electromagnetic radiation of or thermally treating the composition(s).

25. The method of forming an object or an article of manufacture of claim 21, wherein the method is an additive manufacturing method.

26. The method of forming an object or an article of manufacture of claim 25, wherein the additive manufacturing method is a 3-D printing method.

27. The method of forming an object or an article of manufacture of claim 26, wherein the 3- D printing method is digital light processing (DLP), stereolithography (SLA), volumetric printing, UV inkjet printing, or two-photon polymerization printing.

28. The method of forming an object or an article of manufacture of claim 21, further comprising functionalizing the object or the article of manufacture.

29. The method of forming an object or an article of manufacture of claim 21, further comprising one or more post-irradiation or post- thermal treatment process(es) chosen from (i) in the case of an object or an article of manufacture formed by irradiation, irradiating or thermally-treating the object or the article of manufacture formed by the irradiation; and (ii) in the case of an object or an article of manufacture formed by thermal treatment, irradiating or thermally-treating the object or the article of manufacture formed by the irradiation.

30. An object or an article of manufacture comprising one or more at least partially, substantially, or completely crosslinked macromer(s) of claim 1.

31. The object or the article of manufacture of claim 30, wherein the article of manufacture is a porous scaffold, at least a part or portion of a surgical prosthesis, at least a part or portion of a wearable electronic object or device, at least a part or portion of an earbud insert, or at least a part or portion of a microfluidic device.

32. The object or the article of manufacture of claim 30, wherein the object or the article of manufacture is porous.

33. The object or the article of manufacture of claim 30, wherein the object or the article of manufacture comprises an interpenetrating network comprising a first network comprising the one or more at least partially, substantially, or completely crosslinked macromer(s) of claim 1 and a second network comprising one or more at least partially, substantially, or completely crosslinked polymer(s), wherein the first network and the second network are interpenetrating networks.

Images