Preparation method of two-component 3D printing elastomer material containing microcapsule structure

Abstract

The invention discloses a preparation method of a two-component 3D printing elastomer material containing a microcapsule structure, and relates to the technical field of 3D printing materials.The two-component 3D printing elastomer material comprises a component A and a component B. The component A comprises a photocuring oligomer, a chain extender and a flatting agent, and the component B comprises a modified photoinitiator, a curing agent and a polycaprolactone microcapsule. A capsule shell of the polycaprolactone microcapsule is polycaprolactone, and a capsule core of the polycaprolactone microcapsule is a polyurethane prepolymer and epoxy resin. Compared with the prior art, the two-component 3D printing elastomer material provided by the invention has the advantages that the component A and the component B are respectively stored before use and are mixed during use, the reaction among the components in the storage process can be avoided, so that the storage period is prolonged, in addition, TiO2 modified Irgacure 819 has higher photocuring rate, and rapid photocuring can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of 3D printing materials, and in particular relates to a method for preparing a two-component 3D printing elastomer material containing a microcapsule structure. Background Art

[0002] In recent years, with the rapid development of additive manufacturing technology, namely 3D printing, its application in industrial production and innovative design has become increasingly widespread. 3D printing technology builds three-dimensional objects by stacking materials layer by layer, providing unprecedented freedom for the design and manufacture of complex structures. In particular, this technology has shown great potential in the field of elastomeric materials. Elastomers are indispensable in many applications due to their excellent elasticity and deformation ability, such as personalized medical devices, advanced insoles and soft robotic components.

[0003] Traditional elastomer manufacturing methods, such as hot pressing or injection molding, are often limited by molds, which makes it difficult to manufacture complex geometric structures and is costly in small batches. With the advancement of 3D printing technologies such as FDM (fused deposition modeling), SLA (stereolithography) and SLS (selective laser sintering), it has become possible to quickly manufacture elastomer parts with complex geometries directly using digital models. These technologies not only simplify the product development process, but also increase the feasibility of customized products. Especially for elastomer parts with complex internal structures or gradient performance requirements, 3D printing provides a cost-effective and flexible solution.

[0004] In the photocuring technology, the photoinitiator generates free radicals by absorbing light energy, which then initiates the polymerization of monomers to form solid materials. However, when oxygen is present, it can react with these free radicals, interrupting the growth of the polymerization chain and preventing the curing reaction from proceeding, thus affecting the printing speed and efficiency. In addition, during the storage of pre-mixed resins, some photoinitiators may chemically react with other components in the resin, affecting the final curing effect.

[0005] Therefore, providing an elastomeric material that is easy to store, has a long storage period and a high photocuring rate is a technical problem that needs to be solved urgently in the art. Summary of the invention

[0006] In view of the problems of short shelf life and low photocuring rate of existing 3D printing elastomer materials, the present invention provides a method for preparing a two-component 3D printing elastomer material containing a microcapsule structure. Specifically, the technical solution of the present invention includes the following contents:

[0007] One of the objects of the present invention is to provide a two-component 3D printing elastomer material containing a microcapsule structure, comprising component A and component B, wherein component A comprises polyethylene glycol diacrylate, a chain extender and a leveling agent, and component B comprises a modified photoinitiator, a curing agent and polycaprolactone microcapsules.

[0008] Furthermore, calculated by weight, the component A includes 20-50 parts of polyethylene glycol diacrylate, 1-5 parts of chain extender and 0.5-1.2 parts of leveling agent; the component B includes 1-2.5 parts of modified photoinitiator, 1-5 parts of curing agent and 25-60 parts of polycaprolactone microcapsules.

[0009] The second object of the present invention is to provide a method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, the preparation method comprising the following steps:

[0010] Preparation of component A: polyethylene glycol diacrylate is dispersed in an organic solvent, a chain extender and a leveling agent are added, and the mixture is stirred and reacted at 40-45° C. for 1-2 hours. After the reaction is completed, the component A is obtained by vacuum degassing.

[0011] Preparation of component B: Disperse the modified photoinitiator in an organic solvent, add the polycaprolactone microcapsules and curing agent after ultrasonic treatment, stir and react in an environment of 40-45° C. for 1-2 hours, and vacuum degasse to obtain component B after the reaction is completed.

[0012] When used, component A and component B are mixed in a weight ratio of component A: component B = 1: 1.5-3 to obtain a two-component 3D printing elastomer material precursor, which is poured into a 3D printer for printing, and then placed in an oven at 120° C. for heating for 5 hours and then naturally cooled to obtain the two-component 3D printing elastomer material.

[0013] Furthermore, the chain extender includes at least one of 1,4-butanediol, ethylene glycol or 1,3-propylene glycol.

[0014] Furthermore, the leveling agent is Tego-410.

[0015] Furthermore, the curing agent is diaminodichlorodiphenylmethane.

[0016] Furthermore, the organic solvent is acetone.

[0017] Furthermore, the ultrasound includes an ultrasound power of 40 to 80 W and an ultrasound time of 15 to 30 min.

[0018] Furthermore, the vacuum degassing time is 30 to 60 minutes.

[0019] Furthermore, the preparation method of the modified photoinitiator comprises the following steps:

[0020] Disperse 10 parts by weight of TiO2 particles in 50 parts by weight of deionized water, add 100 parts by weight of 65% nitric acid solution, stir and react at 80°C for 2 hours, and obtain hydroxylated TiO2 after washing and drying;

[0021] Disperse 10 parts by weight of hydroxylated TiO2 in 50 parts by weight of ethanol, add 5 parts by weight of 3-aminopropyltriethoxysilane, stir and react at 80°C for 4 hours, wash and dry to obtain amino-treated TiO2;

[0022] Disperse 20 parts by weight of Irgacure 819 in 50 parts by weight of acetone, add 10 parts by weight of maleic anhydride and stir for 5 minutes, then add 1 part by weight of triethylamine, control the temperature at 60° C. in a nitrogen atmosphere, and stir for 12 hours to obtain carboxylated Irgacure 819;

[0023] 10 parts by weight of amino TiO2 and 20 parts by weight of carboxylated Irgacure 819 were dispersed in 50 parts by weight of acetone, 10 parts by weight of EDC and 5 parts by weight of NHS were added, and the mixture was stirred and reacted at 60° C. for 2 h to obtain a modified photoinitiator.

[0024] Furthermore, the preparation method of the polycaprolactone microcapsules comprises the following steps:

[0025] 10 parts by weight of polyether polyol are dissolved in 50 parts by weight of N,N-dimethylformamide, 12 parts by weight of diisocyanate and 0.1 parts by weight of dibutyltin dilaurate are added, and the mixture is stirred and reacted at 150° C. for 2 hours in a nitrogen atmosphere to obtain a polyurethane prepolymer; 10 parts by weight of the polyurethane prepolymer and 10 parts by weight of epoxy resin are dissolved in 100 parts by weight of ethyl acetate to obtain a mixed solution; 0.5 parts by weight of Span-80 are dispersed in 100 parts by weight of deionized water, the mixed solution is added, and the mixture is stirred and reacted at 10,000 rpm for 5 minutes to form a stable oil / water emulsion; 20 parts by weight of polycaprolactone are dissolved in 50 parts by weight of chloroform, the mixture is added to the oil / water emulsion, and the mixture is stirred and reacted at 10,000 rpm for 5 minutes to obtain the polycaprolactone microcapsules.

[0026] Furthermore, the diisocyanate includes at least one of 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate.

[0027] Furthermore, the polyether polyol includes at least one of polytetramethylene glycol or polypropylene glycol.

[0028] Furthermore, the epoxy resin is at least one of bisphenol A epoxy resin, brominated epoxy resin and novolac epoxy resin.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The two-component 3D printing elastomer material provided by the present invention can be stored separately to extend the shelf life. When in use, the material is first initially shaped using rapid light curing technology, and then further processed using overheat curing. With the dual curing mechanism of ultraviolet light curing and heat curing, not only can the shrinkage deformation caused by simple heat curing be reduced, but also the material can maintain a high dimensional accuracy in the final cured state.

[0031] (2) TiO2, as an excellent semiconductor material, exhibits significant light absorption ability, especially in the ultraviolet region. TiO2 is connected to Irgacure 819 through an amide bond. The modified Irgacure 819 can effectively absorb more light energy, thereby improving the photoinitiation efficiency. In addition, TiO2 has photocatalytic activity and can generate electron-hole pairs under ultraviolet light irradiation. These electron-hole pairs can promote the decomposition of Irgacure 819, accelerate the generation of free radicals, and reduce the time required for curing, thereby achieving rapid photocuring. By applying 3-aminopropyltriethoxysilane, the dispersibility and compatibility of TiO2 can be improved, and the agglomeration phenomenon can be effectively reduced, thereby further enhancing the overall performance of the material.

[0032] (3) Wrapping the polyurethane prepolymer and epoxy resin inside a low-melting-point capsule shell to form polycaprolactone microcapsules can prevent the contact reaction between the curing agent and the epoxy resin from affecting the effect of 3D printing. At the same time, it can also avoid the contact and reaction between the chain extender and the polyurethane prepolymer during the photocuring process after the components A and B are mixed.

[0033] (4) When the two-component 3D printing elastomer material prepared by the present invention is used, component A and component B are mixed. After being irradiated with ultraviolet light, the modified photoinitiator can initiate the polymerization of polyethylene glycol diacrylate to achieve rapid ultraviolet light curing and high-precision printing. Subsequently, during the thermal curing process, the capsule shell of the polycaprolactone microcapsule melts to release the polyurethane prepolymer and the epoxy resin. At high temperature, the chain extender reacts with the polyurethane prepolymer, and the epoxy resin reacts with the curing agent to perform secondary curing, which can make the cross-linking tighter and improve the overall stability of the elastomer material. DETAILED DESCRIPTION

[0034] The technical solution of the present invention will be clearly and completely described below through the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0035] Unless otherwise specified, the raw materials and reagents used in the present invention are commercially available or can be prepared by known methods.

[0036] Preparation example:

[0037] The preparation method of the modified photoinitiator comprises the following steps:

[0038] Disperse 10 parts by weight of TiO2 particles in 50 parts by weight of deionized water, add 100 parts by weight of 65% nitric acid solution, stir and react at 80°C for 2 hours, and obtain hydroxylated TiO2 after washing and drying;

[0039] Disperse 10 parts by weight of hydroxylated TiO2 in 50 parts by weight of ethanol, add 5 parts by weight of 3-aminopropyltriethoxysilane, stir and react at 80°C for 4 hours, wash and dry to obtain amino-treated TiO2;

[0040] Disperse 20 parts by weight of Irgacure 819 in 50 parts by weight of acetone, add 10 parts by weight of maleic anhydride and stir for 5 minutes, then add 1 part by weight of triethylamine, control the temperature at 60° C. in a nitrogen atmosphere, and stir for 12 hours to obtain carboxylated Irgacure 819;

[0041] 10 parts by weight of amino TiO2 and 20 parts by weight of carboxylated Irgacure 819 were dispersed in 50 parts by weight of acetone, 10 parts by weight of EDC and 5 parts by weight of NHS were added, and the mixture was stirred and reacted at 60° C. for 2 h to obtain a modified photoinitiator.

[0042] The preparation method of polycaprolactone microcapsules comprises the following steps:

[0043] 10 parts by weight of polytetrahydrofuran diol are dissolved in 50 parts by weight of N,N-dimethylformamide, 12 parts by weight of isophorone diisocyanate and 0.1 parts by weight of dibutyltin dilaurate are added, and the mixture is stirred and reacted at 150° C. for 2 hours in a nitrogen atmosphere to obtain a polyurethane prepolymer; 10 parts by weight of the polyurethane prepolymer and 10 parts by weight of bisphenol A epoxy resin are dissolved in 100 parts by weight of ethyl acetate to obtain a mixed solution; 0.5 parts by weight of Span-80 are dispersed in 100 parts by weight of deionized water, the mixed solution is added, and the mixture is stirred and reacted at 10000 rpm for 5 minutes to form a stable oil / water emulsion; 20 parts by weight of polycaprolactone are dissolved in 50 parts by weight of chloroform, the mixture is added to the oil / water emulsion, and the mixture is stirred and reacted at 10000 rpm for 5 minutes to obtain the polycaprolactone microcapsules.

[0044] Embodiment 1:

[0045] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0046] Preparation of component A:

[0047] Weigh 20 parts by weight of polyethylene glycol diacrylate and disperse it in 100 parts by weight of acetone, add 1 part by weight of 1,4-butanediol and 0.5 parts by weight of Tego-410, stir and react at 40°C for 1 hour, perform vacuum degassing for 30 minutes, put the material into barrels, seal it with nitrogen, and store the barrels upside down to obtain component A.

[0048] Preparation of component B:

[0049] Weigh 1 part by weight of the modified photoinitiator and disperse it in 100 parts by weight of acetone, and perform ultrasound at a power of 40 W for 15 minutes. After the ultrasound, add 25 parts by weight of polycaprolactone microcapsules and 1 part by weight of diaminodichlorodiphenylmethane, stir and react at 40° C. for 1 hour, perform vacuum degassing for 30 minutes, discharge the material and put it into a barrel, add nitrogen to seal the package, and store the barrel upside down to obtain component B.

[0050] When in use, component A and component B are mixed in a weight ratio of 1:1.5 to obtain a two-component 3D printing elastomer material precursor containing a microcapsule structure, which is poured into a 3D printer for printing and then placed in an oven at 120°C for heating for 5 hours and then naturally cooled to obtain a two-component 3D printing elastomer material.

[0051] Embodiment 2:

[0052] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0053] Preparation of component A:

[0054] 30 parts by weight of polyethylene glycol diacrylate were weighed and dispersed in 100 parts by weight of acetone, 3 parts by weight of ethylene glycol and 0.8 parts by weight of Tego-410 were added, and the mixture was stirred for reaction at 42° C. for 1.5 hours, and vacuum degassing treatment was performed for 45 minutes. The material was discharged and put into barrels, sealed with nitrogen, and the barrels were stored upside down to obtain component A.

[0055] Preparation of component B:

[0056] Weigh 1.8 parts by weight of modified photoinitiator and disperse it in 100 parts by weight of acetone, and ultrasonicate it at a power of 60 W for 20 minutes. After the ultrasonication, add 50 parts by weight of polycaprolactone microcapsules and 3 parts by weight of diaminodichlorodiphenylmethane, stir and react at 42°C for 1.5 hours, vacuum degassing for 45 minutes, discharge the material and put it into barrels, seal it with nitrogen, and store the barrels upside down to obtain component B.

[0057] When in use, component A and component B are mixed in a weight ratio of 1:2 to obtain a two-component 3D printing elastomer material precursor containing a microcapsule structure, which is poured into a 3D printer for printing and then placed in an oven at 120°C for heating for 5 hours and then naturally cooled to obtain a two-component 3D printing elastomer material.

[0058] Embodiment 3:

[0059] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0060] Preparation of component A:

[0061] 50 parts by weight of polyethylene glycol diacrylate were weighed and dispersed in 100 parts by weight of acetone, 5 parts by weight of 1,3-propylene glycol and 1.2 parts by weight of Tego-410 were added, and the mixture was stirred for reaction at 45° C. for 2 hours, and vacuum degassing treatment was performed for 60 minutes. The material was discharged and loaded into barrels, sealed with nitrogen, and the barrels were stored upside down to obtain component A.

[0062] Preparation of component B:

[0063] Weigh 2.5 parts by weight of the modified photoinitiator and disperse it in 100 parts by weight of acetone, and ultrasonicate it at a power of 80 W for 30 minutes. After the ultrasonication, add 60 parts by weight of polycaprolactone microcapsules and 5 parts by weight of diaminodichlorodiphenylmethane, stir and react at 45°C for 2 hours, vacuum degassing for 60 minutes, discharge the material and put it into a barrel, add nitrogen to seal the package, and store the barrel upside down to obtain component B.

[0064] When in use, component A and component B are mixed in a weight ratio of 1:3 to obtain a two-component 3D printing elastomer material precursor containing a microcapsule structure, which is poured into a 3D printer for printing and then placed in an oven at 120°C for heating for 5 hours and then naturally cooled to obtain a two-component 3D printing elastomer material.

[0065] Embodiment 4:

[0066] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0067] Preparation of component A:

[0068] 35 parts by weight of polyethylene glycol diacrylate were weighed and dispersed in 100 parts by weight of acetone, 5 parts by weight of 1,4-butanediol and 1.2 parts by weight of Tego-410 were added, and the mixture was stirred for reaction at 45° C. for 2 hours, and then vacuum degassing treatment was performed for 40 minutes. The material was discharged and put into barrels, sealed with nitrogen, and the barrels were stored upside down to obtain component A.

[0069] Preparation of component B:

[0070] Weigh 2.5 parts by weight of the modified photoinitiator and disperse it in 100 parts by weight of acetone, and ultrasonicate it at a power of 80 W for 30 minutes. After the ultrasonication, add 50 parts by weight of polycaprolactone microcapsules and 5 parts by weight of diaminodichlorodiphenylmethane, stir and react at 45°C for 2 hours, vacuum degassing for 40 minutes, discharge the material and put it into a barrel, add nitrogen to seal the package, and store the barrel upside down to obtain component B.

[0071] When in use, component A and component B are mixed in a weight ratio of 1:2 to obtain a two-component 3D printing elastomer material precursor containing a microcapsule structure, which is poured into a 3D printer for printing and then placed in an oven at 120°C for heating for 5 hours and then naturally cooled to obtain a two-component 3D printing elastomer material.

[0072] Comparative Example 1:

[0073] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0074] The modified photoinitiator in Example 4 was replaced by Irgacure 819, and the other conditions remained the same as in Example 4.

[0075] Comparative Example 2:

[0076] A method for preparing a two-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0077] The polycaprolactone microcapsules in Example 4 were replaced with urea-formaldehyde microcapsules, and the other conditions were the same as those in Example 4. The method for preparing urea-formaldehyde microcapsules specifically comprises the following steps:

[0078] 40 parts by weight of a 37% formaldehyde aqueous solution is added into a reaction kettle, the pH value is adjusted to 4, 20 parts by weight of urea granules are added, and the mixture is reacted at 60°C for 30 minutes to obtain a urea-formaldehyde resin emulsion; 10 parts by weight of polytetrahydrofuran diol is dissolved in 50 parts by weight of N,N-dimethylformamide, 12 parts by weight of isophorone diisocyanate and 0.1 parts by weight of dibutyltin dilaurate are added, and the mixture is stirred and reacted at 150°C for 2 hours in a nitrogen atmosphere to obtain a polyurethane prepolymer; 10 parts by weight of a polyurethane prepolymer and 10 parts by weight of a bisphenol A epoxy resin are dispersed in 100 parts by weight of ethyl acetate to obtain a mixed solution, 20 parts by weight of the above urea-formaldehyde resin emulsion and 0.5 parts by weight of Span-80 are added, the pH value is adjusted to 4.5, and the mixture is reacted at 60°C for 4 hours to obtain urea-formaldehyde microcapsules.

[0079] Comparative Example 3:

[0080] A method for preparing a single-component 3D printing elastomer material containing a microcapsule structure, specifically comprising the following steps:

[0081] Weigh 2.5 parts by weight of the modified photoinitiator and disperse it in 200 parts by weight of acetone, and ultrasonicate it at a power of 80 W for 30 minutes. After the ultrasonication, add 35 parts by weight of polyethylene glycol diacrylate, 5 parts by weight of 1,4-butanediol, 1.2 parts by weight of Tego-410, 50 parts by weight of polycaprolactone microcapsules and 5 parts by weight of diaminodichlorodiphenylmethane. Stir the reaction at 45° C. for 2 hours, vacuum degassing for 40 minutes, discharge the material and put it into a barrel, add nitrogen to seal the package, and store the barrel upside down to obtain a single-component 3D printing elastomer material precursor.

[0082] When in use, the 3D printing elastomer material precursor is poured into a 3D printer for printing and then placed in an oven at 120°C for heating for 5 hours and then cooled naturally to obtain a single-component 3D printing elastomer material.

[0083] Test Example 1: Viscosity test and curing time test

[0084] Viscosity test: In an environment of 25°C, use NDT-8s digital display rotational viscometer to test in accordance with GB / T1024-1988;

[0085] Curing time: The two-component 3D printing elastomer material precursors prepared in Examples 1 to 4 and Comparative Examples 1 to 2 and the single-component 3D printing elastomer material precursor prepared in Comparative Example 3 were coated onto a pretreated glass sheet using a four-blade wet film preparation apparatus. The coating thickness was 250 μm. The coating was cured by ultraviolet light irradiation. A stopwatch was used to time and record the curing time. The composition irradiated by the laser beam was touched with a finger at a certain pressure. It was considered to be cured when it was no longer sticky.

[0086] The specific test data are shown in Table 1:

[0087] Table 1. Viscosity and curing time test data

[0088]

[0089]

[0090] It can be seen from the data in Table 1 that the viscosity of the two-component 3D printing elastomer materials prepared by Examples 1 to 4 before curing is less than 20 MPa·s, and has good fluidity in an environment of 25°C. In addition, the two-component 3D printing elastomer materials prepared by Examples 1 to 4 have the ability to cure quickly under ultraviolet light irradiation. Therefore, the two-component 3D printing elastomer materials prepared by the present invention can adapt to higher printing speeds and finer printing details.

[0091] Test Example 2: Performance Test

[0092] The two-component 3D printing elastomer materials prepared in Examples 1 to 4 and Comparative Examples 1 to 2 and the single-component 3D printing elastomer material prepared in Comparative Example 3 were respectively tested for tensile strength, impact strength and shrinkage.

[0093] Tensile performance test: refer to GB / T 1040.3-2006 standard, use CMT4204 tensile testing machine for testing, the tensile rate is 20mm / min;

[0094] Impact performance test: refer to GB / T 1843-2008 standard, use XBL-5.5D cantilever beam digital testing machine for testing, impact energy is 5.5J, impact speed is 3.5m / s;

[0095] Shrinkage test: Refer to the density method and use SMK-401 density meter for testing.

[0096] The specific test data are shown in Table 2:

[0097] Table 2. Performance test data

[0098]

[0099]

[0100] It can be seen from the data in Table 2 that the two-component 3D printing elastomer material containing a microcapsule structure prepared by the present invention can be stored for 12-16 months when the two components are stored separately before curing, and has a long storage validity period; after curing, the tensile strength is 38.4-42.9MPa, with good strength performance, and the impact strength is 6.27-7.92KJ / m 2 , showing excellent toughness performance, with a shrinkage rate of only 2.26-3.63%, which can meet the requirements of precise printing.

[0101] The above-described embodiments provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected.

Claims

1. A two-component 3D printing elastomer material containing a microcapsule structure, characterized in that: The invention comprises component A and component B, wherein the component A comprises a photocurable oligomer, a chain extender and a leveling agent, and the component B comprises a modified photoinitiator, a curing agent and polycaprolactone microcapsules.

2. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 1, characterized in that: Calculated by weight, the component A includes 20-50 parts of photocurable oligomer, 1-5 parts of chain extender and 0.5-1.2 parts of leveling agent; the component B includes 1-2.5 parts of modified photoinitiator, 1-5 parts of curing agent and 25-60 parts of polycaprolactone microcapsules.

3. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 1 or 2, characterized in that: The preparation method of the modified photoinitiator comprises the following steps: Disperse 10 parts by weight of TiO2 particles in 50 parts by weight of deionized water, add 100 parts by weight of 65% nitric acid solution, stir and react at 80°C for 2 hours, and obtain hydroxylated TiO2 after washing and drying; Disperse 10 parts by weight of hydroxylated TiO2 in 50 parts by weight of ethanol, add 5 parts by weight of 3-aminopropyltriethoxysilane, stir and react at 80°C for 4 hours, wash and dry to obtain amino-treated TiO2; Disperse 20 parts by weight of Irgacure 819 in 50 parts by weight of acetone, add 10 parts by weight of maleic anhydride and stir for 5 minutes, then add 1 part by weight of triethylamine, control the temperature at 60° C. in a nitrogen atmosphere, and stir for 12 hours to obtain carboxylated Irgacure 819; 10 parts by weight of amino TiO2 and 20 parts by weight of carboxylated Irgacure 819 were dispersed in 50 parts by weight of acetone, 10 parts by weight of EDC and 5 parts by weight of NHS were added, and the mixture was stirred and reacted at 60° C. for 2 h to obtain a modified photoinitiator.

4. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 1 or 2, characterized in that: The capsule shell of the polycaprolactone microcapsule is polycaprolactone, and the capsule core of the polycaprolactone microcapsule comprises polyurethane prepolymer and epoxy resin.

5. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 4, characterized in that: The preparation method of the polycaprolactone microcapsules comprises the following steps: 50 parts by weight of polyether polyol are dissolved in 500 parts by weight of N,N-dimethylformamide, 7 parts by weight of diisocyanate and 0.4 parts by weight of dibutyltin dilaurate are added, and the mixture is stirred and reacted at 150° C. for 4 hours in a nitrogen atmosphere to obtain a polyurethane prepolymer; 10 parts by weight of the polyurethane prepolymer and 10 parts by weight of epoxy resin are dissolved in 100 parts by weight of ethyl acetate to obtain a mixed solution; 5 parts by weight of Span-80 are dispersed in 500 parts by weight of deionized water, the mixed solution obtained above is added, and the mixture is stirred and reacted at 10,000 rpm for 5 minutes to form a stable oil / water emulsion; 20 parts by weight of polycaprolactone are dissolved in 50 parts by weight of chloroform, the mixture is added to the oil / water emulsion, and the mixture is stirred and reacted at 10,000 rpm for 5 minutes to obtain the polycaprolactone microcapsules.

6. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 5, characterized in that: The epoxy resin is at least one of bisphenol A epoxy resin, brominated epoxy resin and novolac epoxy resin.

7. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 1 or 2, characterized in that: The chain extender includes at least one of 1,4-butanediol, ethylene glycol or 1,3-propylene glycol.

8. A two-component 3D printing elastomer material containing a microcapsule structure as claimed in claim 1 or 2, characterized in that: The leveling agent is Tego-410.

9. The method for preparing a 3D printing elastomer material containing a microcapsule structure according to claim 1 or 2, characterized in that: The curing agent is diaminodichlorodiphenylmethane.

10. The method for preparing a 3D printing elastomer material containing a microcapsule structure according to any one of claims 1 to 9, characterized in that: The following steps are involved: Preparation of component A: polyethylene glycol diacrylate is dispersed in an organic solvent, a chain extender and a leveling agent are added, and the mixture is stirred and reacted at 40-45° C. for 1-2 hours. After the reaction is completed, the component A is obtained by vacuum degassing. Preparation of component B: Disperse the modified photoinitiator in an organic solvent, add the polycaprolactone microcapsules and curing agent after ultrasonic treatment, stir and react in an environment of 40-45° C. for 1-2 hours, and vacuum degasse to obtain component B after the reaction is completed. When used, component A and component B are mixed at a weight ratio of component A: component B = 1: 1.5-3 to obtain the two-component 3D printing elastomer material.

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