Functionalized silicone materials for three-dimensional printing

Abstract

To provide: materials for three-dimensional printing that can be used to easily print completely integrated functional objects with limited post-processing and post-assembly; and processes for preparing the same.SOLUTION: A material for three-dimensional printing includes at least one of a functionalized silicone polymer, a functionalized silica particle, or a combination thereof. The functionalized silicone polymer is functionalized with a member of the group consisting of a carboxylic acid, an amine, and combinations thereof. The functionalized silica particle is functionalized with a member of the group consisting of a carboxylic acid, an amine, and combinations thereof. Also provided is a process for preparing the three-dimensional printing material. Further provided is a process for three-dimensional printing use of the material.SELECTED DRAWING: None

Description

Summary of the Invention

[0001] A material for 3D printing, comprising at least one of a functionalized silicone polymer, functionalized silica particles, or a combination thereof, wherein the functionalized silicone polymer is functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, and the functionalized silica particles are functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, is disclosed herein. In embodiments, the hardness of the material is determined by the selection of the concentration of carboxylic acid, the concentration of amine, the ratio of carboxylic acid to amine, or a combination thereof on the functionalized silicone polymer or functionalized silica particles.

[0002] A process for preparing a material for 3D printing, comprising providing at least one of a silicone polymer, silica particles, or a combination thereof, and functionalizing the silicone polymer or silica particles with a member of the group consisting of carboxylic acids, amines, or combinations thereof, is further disclosed.

[0003] A method for 3D printing, comprising providing a material for 3D printing comprising at least one of a functionalized silicone polymer, functionalized silica particles, or a combination thereof, wherein the functionalized silicone polymer is functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, and the functionalized silica particles are functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, arranging the material in one or more layers, and optionally subjecting the arranged material to at least one treatment for hardening or curing the material, is further disclosed.

[0004] Additive manufacturing (also known as 3D printing), as practiced in the industry, has so far primarily concerned the printing of structural features. The main materials used are thermoplastics that provide form but not function. In this field, there is great interest in developing improved materials that can be used to easily print fully integrated functional objects after limited post-processing and assembly. This would enable novel designs, greater complexity, and customization in the manufacturing and consumption of everyday goods.

[0005] There are various three-dimensional (3D) printing processes, including material extrusion, material spraying, stereolithography, selective laser sintering, and others. All specific 3D printing methods require a suitable material that can be processed by the printer and formed into a final object with various properties. Material extrusion 3D printing processes use nozzles to deposit material in layers, with the possibility of preheating the material to assist in distribution. Material spraying processes use a moving print head to deposit droplets of material that will later be cured. Stereolithography processes use liquid photocurable resins that are placed in a vat and selectively cured / hardened by a laser.

[0006] Selective laser sintering (SLS) uses a rasterized laser to scan a polymer powder bed, sintering it to form a solid shape in a hierarchical manner. As the laser beam scans the powder, the powder melts layer by layer due to the rising temperature, and the final portion approaches total density, yielding properties similar to the bulk material (i.e., polymer). Theoretically, all thermoplastic polymers that can be converted into powder form can be processed through this technique; however, in practice, all materials exhibit different behaviors during melting, agglomeration, and solidification, often unpredictably, and often require unique SLS processing parameters. Bed temperature and laser energy input can be selected, for example, based on the processing window of the polymer's thermal profile and its energy absorption. Laser parameters can also be selected based on the particle size and shape of the powder.

[0007] Methods for producing silicone elastomers via 3D printing and additive manufacturing have been described in the art. These processes typically involve crosslinkable / curable silicone materials that are hardened / cured by electromagnetic radiation.

[0008] The development of materials with adjustable properties for 3D printing has been challenging due to the technical requirements of 3D printing, which limit the types of materials that can be produced. In particular, obtaining soft or hard materials with different moduli, elongation, and fracture strengths is difficult and requires multiple raw materials with different properties. One approach to this problem involves printing multiple types of materials and mixing them into a final composite material.

[0009] One embodiment may include printing a first layer of scaffolding fibers onto a base gel substrate using a printer, and placing a first gel layer on top of the printed first layer. Another embodiment may include printing first and second sacrificial fibers onto a base gel substrate using a printer, printing first scaffolding fibers between the first and second sacrificial fibers to form a printed first layer, and placing a first gel layer on top of the printed first layer.

[0010] While currently available 3D printing materials and processes may be suitable for their intended purposes, there is still a need for improved 3D printing materials and processes. Furthermore, there is still a need for more efficient and simplified 3D printing materials and processes, particularly those suitable for larger scales and faster processing times. Furthermore, there is still a need for 3D printing materials and processes that can be adjusted to desired hardness or softness. Furthermore, there is still a need for biocompatible 3D printing materials and processes. Furthermore, there is a need for different hardening / melting processes for materials, particularly silicone elastomers.

[0011] The present invention also describes a material for three-dimensional printing comprising at least one of a functionalized silicone polymer, functionalized silica particles, or a combination thereof, wherein the functionalized silicone polymer is functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, and the functionalized silica particles are functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof.

[0012] The description also includes a process for preparing materials for three-dimensional printing, comprising providing a silicone polymer or silica particles, and functionalizing the silicone polymer or silica particles with a member of the group consisting of carboxylic acids, amines, or combinations thereof.

[0013] The present invention also describes a method for three-dimensional printing, which provides a material for three-dimensional printing comprising at least one of a functionalized silicone polymer, functionalized silica particles, or a combination thereof, wherein the functionalized silicone polymer is functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof, and the functionalized silica particles are functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof; the method comprises arranging the material in one or more layers; and optionally, subjecting the arranged material to at least one treatment for hardening or curing the material. [Modes for carrying out the invention]

[0014] To provide three-dimensional printing materials that can be hardened without requiring UV (ultraviolet) or thermal curing, silicone and silica materials enhanced (or functionalized) by at least one of carboxylic acid groups, amine groups, or combinations thereof are described herein. In embodiments, the three-dimensional printing material can be hardened by intermolecular interactions between functional groups. Three-dimensional printing materials containing these functional additives have the advantages of not requiring initiators / catalysts, being oxygen-insensitive, and not being limited by material thickness. In certain embodiments, the silicone or silica material is functionalized with both carboxylic acid groups and amine groups. Multiple functional groups incorporated into the polymer chain result in strong intermolecular interactions between polymers that contribute to the physical hardening of the material.

[0015] In the embodiments, silicones functionalized with carboxylic acid groups and amine groups are provided, and optionally, UV curing, thermal curing, or a combination thereof is used to produce both soft and hard materials via 3D printing. The functional groups in the silicone precursor provide mechanical strengthening and hardening of the resulting material. Enhanced hardness and toughness can be achieved by adding silica particles having amine and carboxylic acid groups or functionalized silica particles to the silicone material.

[0016] This functionalized material offers the advantages of three-dimensional printing, including (1) enabling a variety of soft and hard materials that can be easily obtained by changing the concentration and ratio of carboxylic acid groups and amine groups, (2) physical hardening of the material due to intermolecular interactions between functional groups, (3) a two-step material hardening process comprising a first step of physical hardening via intermolecular interactions of functional groups and a second step of chemical hardening, UV hardening, or thermal hardening, and (4) mechanical hardening independent of the material thickness and temperature (e.g., UV hardening has a thickness limitation).

[0017] In the embodiment, the material for 3D printing comprises a functionalized silicone polymer or functionalized silica particles, the silicone polymer or silica particles being functionalized with members of the group consisting of carboxylic acid groups, amine groups, and combinations thereof. In the embodiment, the hardness of the material is determined by the selection of the concentration of carboxylic acid groups, the concentration of amine groups, the ratio of carboxylic acid groups to amine groups, or combinations thereof on the functionalized silicone polymer or functionalized silica particles. In the embodiment, the 3D printing material has the property of hardening without requiring ultraviolet irradiation.

[0018] Functionalized silicone polymers or functionalized silica particles can be functionalized with any suitable or desired hardening additive. In embodiments, the functionalized silicone polymer or functionalized silica particles are functionalized by chemically modifying the silicone polymer or silica with a carboxylic acid group-containing additive, an amine group-containing additive, or a combination thereof.

[0019] In the embodiment, the functionalized silicone polymer or functionalized silica particles are functionalized with at least one member of the group consisting of carboxylic acid-containing compounds, amine-containing compounds, and combinations thereof.

[0020] Any suitable or desired silicone polymer can be selected for the three-dimensional printing material described herein. In embodiments, the silicone polymer is a member of the group consisting of poly(dimethylsiloxane), vinyl-terminated polydimethylsiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, (methacrylateoxypropyl)methylsiloxane-dimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

[0021] In some embodiments, the starting material for preparing the functionalized silicone is a poly(dimethylsiloxane) copolymer having an amino group (aminoPDMS). In certain embodiments, the functionalized silicone polymer is a member of the group consisting of aminoethylaminopropyl-methylsiloxanedimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

[0022] The functionalized silicone polymer may be present in any preferred or desired amount. In embodiments, the functionalized silicone polymer is selected in an amount of about 10 to about 100, or about 20 to about 80, or about 40 to about 50% by weight, based on the total weight of the silicone polymer used. In embodiments, the functionalized silicone copolymer (starting material) contains about 5 to about 50% aminopropyl-methylsiloxane monomer units and about 5 to about 25% aminopropyl-methylsiloxane monomer units, based on the total number of moles of silicone monomers.

[0023] Amino-functionalized silicone polymers or copolymers can be further modified with carboxylic acid groups by adding various anhydride-containing molecules. The type of anhydride molecule selected affects the final material properties. For example, (2-dodecene-1-yl)succinic anhydride contains long hydrophobic alkyl chains that can impart further flexibility and hydrophobicity to the material. Additional functional groups can be incorporated into aminosilicones using different types of substituted anhydride-containing molecules. For example, reacting 1,2,4-benzenetricarboxylic acid anhydride with aminosilicone can produce a polymer functionalized with twice the amount of carboxylic acid groups compared to unsubstituted anhydride molecules such as succinic anhydride. 2,3-pyridinedicarboxylic acid anhydride is a building block that can bond to the amine groups of aminosilicones, and its derivatives have been shown to have antimicrobial properties. (Ammar, YAet al. "Reactivity of 2,3-Pyridine Dicarboxylic Anhydride Towards some Nitrogen Nucleophilic Reagents: Synthesis and Antimicrobial Evaluation of some Pyridine Carboxamide and Pyrrolo [3,4-B]Pyridine-5,7-Dione Derivatives." Chemical Sciences Journal, CSJ-16 (2011).

[0024] In the embodiment, the functionalized silicone polymer is a member of the group consisting of aminoethylaminopropyl-methylsiloxanedimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

[0025] Silicone copolymers having amine groups are further functionalized with carboxylic acid groups by adding anhydride-containing molecules selected from the group consisting of maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, glutaric anhydride, (2-dodecen-1-yl)succinic anhydride, 1,2,4-benzenetricarboxylic acid anhydride, and combinations thereof.

[0026] Epoxy-functionalized silicone polymers or copolymers, in embodiments, poly(dimethylsiloxane) copolymers, are suitable starting materials for the preparation of amine-functionalized three-dimensional printing materials. In embodiments, the functionalized silicone polymer is an epoxy-functionalized silicone polymer selected from the group consisting of (epoxypropoxypropyl)methylsiloxane-dimethylsiloxane copolymer, (epoxycyclohexylethyl)methylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

[0027] The epoxy-functionalized silicone polymer may be present in any preferred or desired amount. In embodiments, the epoxy-functionalized silicone polymer is selected in an amount of about 10 to about 100, or about 20 to about 80, or about 40 to about 50% by weight, based on the total weight of the silicone copolymer used. In embodiments, epoxypropoxypropyl-methylsiloxane monomers are selected in amounts of about 5 to about 50 or about 5 to about 25 monomer units, moles, based on the total number of moles of silicone monomers.

[0028] In the embodiment, the functionalized silicone polymer is an epoxy-functionalized silicone polymer, and the epoxy-functionalized silicone polymer further includes amine groups incorporated into the epoxy-functionalized silicone polymer by adding an amine-containing nucleophile.

[0029] Any suitable or desired amine-containing nucleophile can be selected. In embodiments, the amine-containing nucleophile is selected from the group consisting of 3-(dimethylamino)-1-propylamine, 1-(2-aminoethyl)piperazine, N-(3-aminopropyl)-diethanolamine, allantoin, and combinations thereof.

[0030] The functionalized silica particles can be prepared according to a modified Stober synthesis method using an amine group-containing silica precursor. Any suitable or desired amine group-containing silica precursor can be selected. In embodiments, the amine group-containing silica precursor is selected from the group consisting of aminopropyltriethoxysilane, aminopropyltrimethoxysilane, and combinations thereof.

[0031] In embodiments, the functionalized silica particles are amino-functionalized silica particles comprising the reaction product of a member of the group consisting of aminopropyltriethoxysilane, tetraethyl orthosilicate, aminopropyltrimethoxysilane, tetramethyl orthosilicate, and combinations thereof.

[0032] The resulting silica particles can subsequently be modified with an anhydride molecule such as maleic anhydride to form carboxylic acid-functionalized silica particles.

[0033] Thus, in embodiments, the functionalized silica particles are amino-functionalized silica particles. In embodiments, the functionalized silica particles are amino-functionalized silica particles further functionalized with a carboxylic acid.

[0034] In embodiments, the functionalized silica particles are amino-functionalized silica particles further functionalized with an anhydride-containing molecule or a carboxylic acid-containing molecule,

[0035] The anhydride-containing molecule is selected from the group consisting of maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, glutaric anhydride, (2-dodecen-1-yl)succinic anhydride, and combinations thereof,

[0036] The carboxylic acid-containing molecule is selected from the group consisting of maleic acid, itaconic acid, phthalic acid, glutaric acid, (2-dodecen-1-yl)succinic acid, and combinations thereof.

[0037] The three-dimensional printing materials described herein may further contain silicone elastomer resins. Therefore, additional types of silicones, in embodiments, UV-curable silicones, thermosetting silicones, or combinations thereof, can be mixed with one or more of the functionalized silicone polymers or functionalized silica particles to form the three-dimensional printing material. In embodiments, one or more of the functionalized silicone polymers or functionalized silica particles can be mixed with typical silicone resins, such as silicone elastomer resins, to modify the final properties. Any suitable or desired silicone elastomer resin can be selected. In embodiments, the silicone elastomer resin is selected from the group consisting of vinyl-terminated polydimethylsiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, (methacrylateoxypropyl)methylsiloxane-dimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

[0038] The functionalized silicone materials described herein can be prepared by any suitable or desired process, which involves mixing functionalized silicone polymer particles with silica particles and a silicone elastomer resin. In embodiments, the functionalized silicone materials described herein can be prepared according to a two-step process comprising: (1) functionalization of silicone polymer chains and / or silica particles having amine groups and carboxylic acid groups; and (2) three-dimensional material of the functionalized silicone polymer and / or silica particles, optionally incorporated into UV-curable or thermosetting silicone.

[0039] In embodiments, the process for preparing materials for three-dimensional printing as described herein includes providing a silicone polymer or silica particles and functionalizing the silicone polymer or silica particles with a member of the group consisting of carboxylic acids, amines, or combinations thereof. In certain embodiments, the functionalization includes functionalizing the silicone polymer or silica particles with at least one member of the group consisting of carboxylic acid-containing compounds, amine-containing compounds, and combinations thereof.

[0040] This specification further provides methods for three-dimensional printing. Any preferred or desired printing method may be selected for the three-dimensional printing material.

[0041] A method for three-dimensional printing provides a material for three-dimensional printing comprising a functionalized silicone polymer or functionalized silica particles, wherein the silicone polymer or silica particles are functionalized with a member of the group consisting of carboxylic acids, amines, and combinations thereof; arranging the material in one or more layers; and optionally, subjecting the arranged material to at least one treatment for curing the material.

[0042] In embodiments, exposing a material to at least one treatment for curing the material includes curing the material with heat or ultraviolet irradiation. In embodiments, exposing a material to at least one treatment for curing the material includes a two-step process comprising a first step comprising physical hardening via intermolecular interactions of functional groups, and a second step comprising exposing the material to chemical curing, ultraviolet irradiation, thermal curing, or a combination thereof. Exposing a material to at least one treatment for curing the material may include curing the material without the use of ultraviolet irradiation. The materials and methods herein enable mechanical hardening that is independent of the thickness and temperature of the material and offers advantages over UV-dependent systems where the thickness is limited.

[0043] In this embodiment, the material for three-dimensional printing can be used in a material extrusion method in which a viscous fluid or paste is dispensed through a nozzle.

[0044] The following are examples submitted to further define the various types of the present disclosure. Examples 1 and 2 describe the preparation of functionalized silicone materials that have been carried out. Examples 3 to 8 are hypothetical examples describing the modification and formulation of functionalized silicone materials. These examples are illustrative only and are not intended to limit the scope of the present disclosure. Unless otherwise stated, parts and percentages are by weight.

[0045] Poly(dimethylsiloxane) copolymers can be obtained from Gelest Inc. [Examples]

[0046] Preparation of silicone materials functionalized with amine groups and carboxylic acid groups.

[0047] Amine-functionalized silicone copolymers, specifically 18-24% aminoethylaminopropylmethylsiloxane-dimethylsiloxane copolymers at 300-500 cSt, were obtained from Gelest, Inc. These amine-functionalized silicone copolymers were further modified with carboxylic acid groups. Two grams of 18-24% aminoethylaminopropylmethylsiloxane-dimethylsiloxane copolymer were dissolved in two milliliters of tetrahydrofuran at room temperature with a stirring speed of 500 rpm (RPM). 0.14 grams of succinic anhydride were dissolved in one milliliter of tetrahydrofuran and added dropwise to the polymer solution, followed by stirring for 24 hours. 0.6 grams of hexamethyldisilazane-treated silica were dispersed in two milliliters of tetrahydrofuran and added to the polymer solution, followed by stirring at 500 rpm for 2 hours. The resulting mixture was dried at room temperature to form a hardened elastomer material. The material was then dried under vacuum. The material hardness was tested using a Shore durometer type A-2, and the material had a hardness of Shore 70A. [Examples]

[0048] A functionalized silicone material was prepared according to the process of Example 1. The amount of succinic anhydride used was 0.27 grams. After drying, the material hardened and had a hardness of Shore A79. [Examples]

[0049] Amino-functionalized silica particles. A silica precursor mixture is prepared by mixing 0.2 grams of tetramethyl orthosilicate and 0.2 grams of aminopropyltriethoxysilane. This mixture is added dropwise to 0.1 grams of an aqueous solution of Triton® X-100 (4-(1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol) in 10 ml of deionized water, while vigorously stirring. The solution is stirred at room temperature for 24 hours. The particles are purified by centrifugation. [Examples]

[0050] Carboxylic acid-functionalized silica particles. The product from Example 3 is mixed with 20 milligrams of maleic anhydride in an acetone solution. The solution is stirred at room temperature for 24 hours. [Examples]

[0051] A thermosetting functionalized silicone material having the components shown in Table 1 is prepared.

[0052] [Table 1] [Examples]

[0053] A comparative example of a thermosetting silicone material having the components shown in Table 2 was prepared.

[0054] [Table 2] [Examples]

[0055] Prepare a UV-curable functionalized silicone material having the components shown in Table 3.

[0056] [Table 3] [Examples]

[0057] A comparative example of a UV-curable silicone material having the components shown in Table 4 was prepared.

[0058] [Table 4]

[0059] Therefore, silicone materials are provided that have carboxylic acid groups and amine groups having intermolecular interactions in the form of ionic and hydrogen bonds, which are not present in comparative silicone materials. These additional interactions between functionalizing components contribute to the physical hardening of the material.

Claims

1. A material for three-dimensional printing, comprising: comprising at least one of a functionalized silicone polymer, a functionalized silica particle, or a combination thereof; the functionalized silicone polymer is functionalized with a member of the group consisting of a carboxylic acid, an amine, and combinations thereof; The material, wherein the functionalized silica particles are functionalized with a member of the group consisting of a carboxylic acid, an amine, and combinations thereof.

2. The material of claim 1 , wherein the material has the property of hardening without the need for ultraviolet radiation.

3. 10. The material of claim 1, wherein the functionalized silicone polymer or functionalized silica particle is functionalized with at least one member of the group consisting of a carboxylic acid-containing compound, an amine-containing compound, and combinations thereof.

4. 10. The material of claim 1, wherein the silicone polymer is a member of the group consisting of poly(dimethylsiloxane), vinyl-terminated polydimethylsiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, (methacryloxypropyl)methylsiloxane-dimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

5. 10. The material of claim 1, wherein the functionalized silicone polymer is a member of the group consisting of aminoethylaminopropyl-methylsiloxanedimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

6. the functionalized silicone polymer is a member of the group consisting of aminoethylaminopropyl-methylsiloxanedimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof; 10. The material of claim 1, wherein the functionalized silicone polymer is further functionalized with carboxylic acid groups by adding an anhydride-containing molecule selected from the group consisting of maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, glutaric anhydride, (2-dodecen-1-yl)succinic anhydride, 1,2,4-benzenetricarboxylic anhydride, 2,3-pyridinedicarboxylic anhydride, and combinations thereof.

7. 10. The material of claim 1, wherein the functionalized silicone polymer is an epoxy-functionalized silicone polymer selected from the group consisting of (epoxypropoxypropyl)methylsiloxane-dimethylsiloxane copolymer, (epoxycyclohexylethyl)methylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

8. 10. The material of claim 1, wherein the functionalized silicone polymer is an epoxy-functionalized silicone polymer, the epoxy-functionalized silicone polymer further comprising amine groups that are incorporated into the epoxy-functionalized silicone polymer by adding an amine-containing nucleophile.

9. 9. The material of claim 8, wherein the amine-containing nucleophile is selected from the group consisting of 3-(dimethylamino)-1-propylamine, 1-(2-aminoethyl)piperazine, N-(3-aminopropyl)-diethanolamine), allantoin, and combinations thereof.

10. 10. The material of claim 1, wherein the functionalized silica particles are amino-functionalized silica particles comprising the reaction product of a member of the group consisting of aminopropyltriethoxysilane, tetramethylorthosilicate, aminopropyltrimethoxysilane, tetramethylorthosilicate, and combinations thereof.

11. 10. The material of claim 1, wherein the functionalized silica particles are amino-functionalized silica particles further functionalized with a carboxylic acid.

12. the functionalized silica particles are amino-functionalized silica particles further functionalized with anhydride-containing molecules or carboxylic acid-containing molecules; the anhydride-containing molecule is selected from the group consisting of maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, glutaric anhydride, (2-dodecen-1-yl)succinic anhydride, and combinations thereof; 10. The material of claim 1, wherein the carboxylic acid-containing molecule is selected from the group consisting of maleic acid, itaconic acid, phthalic acid, glutaric acid, (2-dodecen-1-yl)succinic acid, and combinations thereof.

13. 10. The material of claim 1, further comprising a silicone elastomer resin selected from the group consisting of vinyl-terminated polydimethylsiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, (methacryloxypropyl)methylsiloxane-dimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

14. 1. A process for preparing a material for three-dimensional printing, comprising: providing at least one of a silicone polymer, silica particles, or a combination thereof; and functionalizing the silicone polymer or silica particles with a member of the group consisting of a carboxylic acid, an amine, or a combination thereof.

15. 15. The process of claim 14, wherein functionalizing comprises functionalizing the silicone polymer or silica particle with at least one member of the group consisting of a carboxylic acid-containing compound, an amine-containing compound, an anhydride compound, or a combination thereof.

16. 15. The process of claim 14, wherein the silicone polymer is a member of the group consisting of poly(dimethylsiloxane), vinyl-terminated polydimethylsiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, (methacryloxypropyl)methylsiloxane-dimethylsiloxane copolymer, aminopropylmethylsiloxane-dimethylsiloxane copolymer, and combinations thereof.

17. 1. A method for three-dimensional printing, comprising: providing a material for three-dimensional printing, the material comprising at least one of a functionalized silicone polymer, a functionalized silica particle, or a combination thereof, wherein the functionalized silicone polymer is functionalized with a member of the group consisting of a carboxylic acid, an amine, and a combination thereof, and the functionalized silica particle is functionalized with a member of the group consisting of a carboxylic acid, an amine, and a combination thereof; disposing said material in one or more layers; Optionally, exposing the disposed material to at least one treatment to harden or harden the material.

18. 20. The process of claim 17, wherein exposing the material to at least one treatment to harden the material comprises a two-step process comprising a first step comprising physical hardening via intermolecular interactions of functional groups and a second step comprising exposing the material to chemical hardening, ultraviolet radiation, thermal hardening, or a combination thereof.

19. 18. The process of claim 17, wherein exposing the material to at least one treatment to harden the material comprises hardening the material with heat or ultraviolet radiation.

20. 18. The process of claim 17, wherein the functionalized silicone polymer or functionalized silica particle is functionalized with at least one member of the group consisting of a carboxylic acid-containing compound, an amine-containing compound, an anhydride compound, and combinations thereof.