High-strength high-temperature-resistant light-cured resin for 3D printing and preparation method of high-strength high-temperature-resistant light-cured resin

Abstract

The invention relates to the technical field of light-cured resin, in particular to high-strength and high-temperature-resistant light-cured resin for 3D printing and a preparation method thereof. The high-strength and high-temperature-resistant light-cured resin comprises the following raw materials in parts by weight: 40-60 parts of a resin material, 40-60 parts of inorganic powder and 1-5 parts of a reinforcing material. According to the invention, a rigid molecular skeleton formed by a methacrylate monomer with high benzene ring content and bisphenol A epoxy resin together and an interpenetrating network generate a molecular lock effect, a huge benzene ring provides an extremely high motion energy barrier, the interpenetrating network limits chain segment motion from a topological structure, and the surface-functionalized aramid fiber and an in-situ grown ZIF-8 structure thereof have the advantages that the surface-functionalized aramid fiber and the in-situ grown ZIF-8 structure can be used for modifying the surface-functionalized aramid fiber and the in-situ grown ZIF-8 structure of the surface-functionalized aramid fiber; the three-dimensional network structure of the three-dimensional network structure provides reliable thermal mechanical support for the material, and it is ensured that a printed piece keeps excellent dimensional stability and mechanical performance in a high-temperature environment, and the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure of the three-dimensional network structure.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of light-cured resin, in particular to high-strength high-temperature-resistant light-cured resin for 3D printing and a preparation method thereof. BACKGROUND

[0002] The light-cured 3D printing technology is a production and manufacturing technology for manufacturing products by using the energy of a near-ultraviolet light source to excite free radicals to cause polymerization. The light-cured 3D printing technology can greatly increase the design freedom of products, greatly shorten the time and cost from design to manufacturing, and the produced products do not need additional cutting, polishing and surface treatment, so the light-cured 3D printing technology is widely used in the fields of dentistry and the like. The core of the light-cured 3D printing technology is light-cured resin. The light-cured resin causes the polymerization of monomers and oligomers by exciting initiators to generate free radicals through a light source, so as to be shaped and cured.

[0003] In the prior art, the conventional light-cured resin, such as acrylate resin, generally has the problems of poor heat resistance and insufficient mechanical strength, which seriously limits the application thereof in high-temperature and high-load working conditions.

[0004] Based on this, the application provides high-strength high-temperature-resistant light-cured resin for 3D printing and a preparation method thereof. SUMMARY

[0005] The application aims to provide high-strength high-temperature-resistant light-cured resin for 3D printing and a preparation method thereof. The 3D printed parts made of the light-cured resin prepared by the application not only have good bending strength and bending modulus performance, but also have excellent thermal deformation and Shore hardness.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme: high-strength high-temperature-resistant light-cured resin for 3D printing, which comprises the following raw materials in parts by weight: 40-60 parts of resin material, 40-60 parts of inorganic powder and 1-5 parts of reinforcing material. The resin material is prepared by mixing the first additive and the second additive at a mass ratio of 80-90:10-20; The first additive is prepared by mixing high-benzene ring content methacrylate monomer, active diluent and photoinitiator at a mass ratio of 40-60:30-60:1-5; The second additive is prepared by mixing bisphenol A type epoxy resin and thermal initiator at a mass ratio of 95-99:1.

[0007] Preferably, the high-benzene-ring-content methacrylate monomer is prepared by the following method: tetra(4-hydroxyphenyl)methane and 2-chloroethanol are mixed in a molar ratio of 1-4.2:1-5, and a first catalyst is added. The mixture is reacted at 85-95°C for 12-24 h to obtain a first crude product. The first crude product is dissolved in dichloromethane and washed with 5-10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The first organic phase is separated and distilled under reduced pressure to remove dichloromethane, resulting in an intermediate product. The intermediate product is then mixed with methacryloyl chloride in a molar ratio of 1-4.2:1-4.5, and a second catalyst is added. The mixture is reacted at room temperature for 28-36 h to obtain a second crude product. The second crude product is dissolved in dichloromethane and washed with 5-10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The second organic phase is separated and distilled under reduced pressure to remove dichloromethane, resulting in the final product, thus completing the preparation of the high-benzene-ring-content methacrylate monomer.

[0008] Preferably, the mass ratio of the first crude product to dichloromethane is 1:8-12, the mass ratio of the second crude product to dichloromethane is 1:5-8, the first catalyst is sodium hydroxide, the second catalyst is triethylamine, the molar ratio of triethylamine to methacrylamide chloride is 1-1.5:1, and the molar ratio of sodium hydroxide to 2-chloroethanol is 1-2:1.

[0009] Preferably, the inorganic powder is spherical silicon dioxide.

[0010] Preferably, the reinforcing material is prepared by the following method: Commercial aramid fibers are shredded and added to a reactor along with anhydrous dimethyl sulfoxide. The mixture is stirred at 1000-2000 r / min for 30-40 min, then potassium hydroxide is slowly added, and the stirring speed is increased to 2000-3000 r / min for 4-6 h. Subsequently, the mixture is stirred at 200-300 r / min for 7 days at room temperature to obtain a first dispersion. 2-Aminoterephthalic acid is then added to the reactor containing the first dispersion, and the mixture is stirred at 60°C. After stirring at 100-300 rpm for 10-12 hours, the mixture was cooled to room temperature to obtain a second dispersion. The second dispersion and the first mixed solution were added to a three-necked flask, which was then placed in an ice-water bath at 0-5°C and stirred at 800-1000 rpm. During stirring, the second solution was slowly added dropwise at 2 mL / min. The reaction was continued for 1-1.2 hours while maintaining the temperature and stirring speed to obtain a gel product. The gel product was then broken into 1 cm pieces using a spatula. 3Small pieces of the mixture were added to a glass beaker with anhydrous DMF and allowed to stand for 6-7 hours. Then, the mixture was filtered using a Buchner funnel to retain the solid material. This process of soaking in anhydrous DMF and filtering was repeated 3-5 times to obtain the first resin. The first resin and anhydrous ethanol were then added to a glass flask and allowed to stand for 4-5 hours. This process of soaking in anhydrous ethanol and filtering was repeated 3-5 times to obtain the second resin. The second resin was then dried in a supercritical CO2 drying kettle to complete the preparation of the reinforcing material.

[0011] Preferably, during the drying process, the supercritical CO2 drying vessel is set to a temperature of 40°C and a pressure of 8MPa. First, the inlet and outlet valves are closed, and the system is kept at a constant temperature and pressure for 2-3 hours. Then, while maintaining 40°C and 8MPa, the system slowly opens the outlet valve and continuously pumps in fresh supercritical CO2 for 2-4 hours. After that, the pressure is slowly released to atmospheric pressure within 1-2 hours.

[0012] Preferably, the first mixed solution is prepared by mixing zinc nitrate hexahydrate, anhydrous DMF and deionized water in a mass ratio of 1:120-130:6-7, and the second mixed solution is prepared by mixing trimesoyl chloride and anhydrous DMF in a mass ratio of 1:40-50.

[0013] Preferably, in the preparation of the first dispersion, the mass ratio of commercial aramid fiber, anhydrous dimethyl sulfoxide, and potassium hydroxide is 1:1000-1200:1.4-1.6, the mass ratio of 2-aminoterephthalic acid to commercial aramid fiber is 4-6:1, the mass ratio of gel fragmentation product to anhydrous DMF in the washing process of the gel product is 1:40-60, the mass ratio of the first adhesive to anhydrous ethanol in the solvent replacement process of the first adhesive is 1:35-45, and the volume ratio of the second dispersion, the first mixed solution, and the second solution is 18-22:7-9:1.

[0014] Preferably, the thermal initiator is triarylsulfonium hexafluoroantimonate, the reactive diluent is hydroxyethyl methacrylate, and the photoinitiator is photoinitiator 1173.

[0015] A method for preparing a high-strength, high-temperature-resistant photocurable resin for 3D printing. Step 1: Mix the high-benzene-ring content methacrylate monomer, reactive diluent, and photoinitiator in a specified ratio, and mechanically stir under light-protected conditions until completely dissolved and homogeneous to obtain the first additive; mix the bisphenol A epoxy resin and thermal initiator in a specified ratio, and mechanically stir until completely dissolved and homogeneous to obtain the second additive; mix the first additive and the second additive in a specified ratio, and mechanically stir until homogeneous to obtain the resin material. Step 2: Add the resin, inorganic powder and reinforcing material together to a planetary mixer. First, mix at 100-300 r / min for 10-12 min, then increase the speed to 1000-2000 r / min and mix for 30-60 min to obtain a slurry. Step 3: Transfer the slurry to a vacuum degassing chamber and remove bubbles for 15-30 minutes under a vacuum of -0.095MPa to -0.1MPa. Then discharge the slurry to complete the preparation of high-strength, high-temperature resistant photocurable resin for 3D printing.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. In this invention, the photosensitive resin network provides the basis for rapid prototyping, while the epoxy resin forms high-density crosslinks in the post-curing stage, significantly improving the overall crosslinking degree. The rigid molecular skeleton composed of high benzene ring content methacrylate monomers and bisphenol A type epoxy resin generates a molecular locking effect with the interpenetrating network. The large benzene rings provide extremely high kinetic energy barriers, while the interpenetrating network restricts chain segment movement from a topological perspective. The surface-functionalized aramid fibers and their in-situ grown ZIF-8 structure form a strong interfacial bond with the resin matrix. These rigid reinforcing phases can remain stable at high temperatures, effectively suppressing the thermal movement of resin molecular chains. At the same time, their three-dimensional network structure provides reliable thermomechanical support for the material, ensuring that the printed parts maintain excellent dimensional stability and mechanical properties in high-temperature environments.

[0017] 2. In this invention, a dual-scale reinforcement system is constructed through the synergistic effect of spherical silica and surface-functionalized aramid fibers. ZIF-8 structures are grown in situ on the surface of specially treated aramid fibers to form a unique micro-nano composite reinforcement, which greatly increases the interfacial contact area. Furthermore, the amino and carboxyl active functional groups introduced on the surface of the reinforcement form a strong chemical bond network with the resin matrix, including ring-opening reactions with epoxy groups and hydrogen bonding with ester groups. This achieves a qualitative transformation from traditional physical adsorption to chemical bonding. This strong interfacial bonding ensures efficient stress transfer between components and improves the mechanical properties of the photocurable resin. Attached Figure Description

[0018] Figure 1 This invention presents a flowchart of a high-strength, high-temperature-resistant photocurable resin for 3D printing and its preparation method; Figure 2 This is the structure of the high benzene ring content methacrylate monomer in this invention; Figure 3 This is the synthetic route for high benzene ring content methacrylate monomers in this invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that the raw materials used in the following embodiments are all commercially available. Anhydrous DMF is N,N-dimethylformamide.

[0021] Example 1: A high-strength, high-temperature-resistant photocurable resin for 3D printing, comprising the following parts by weight of raw materials: 40 parts resin material, 40 parts inorganic powder and 1 part reinforcing material; The resin material is prepared by mixing the first additive and the second additive in a mass ratio of 80:10; The first additive is prepared by mixing high benzene ring content methacrylate monomer, reactive diluent and photoinitiator in a mass ratio of 40:30:1; The second additive is prepared by mixing bisphenol A type epoxy resin and thermal initiator at a mass ratio of 95:1.

[0022] The high-benzene-ring-content methacrylate monomer was prepared by the following method: tetra(4-hydroxyphenyl)methane and 2-chloroethanol were mixed in a molar ratio of 1:1, and a first catalyst was added. The mixture was reacted at 85°C for 12 h to obtain a first crude product. The first crude product was dissolved in dichloromethane and washed with 5% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The first organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding an intermediate product. The intermediate product was then mixed with methacryloyl chloride in a molar ratio of 1:1, and a second catalyst was added. The mixture was reacted at room temperature for 28 h to obtain a second crude product. The second crude product was dissolved in dichloromethane and washed with 5% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The second organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding the final product. This completed the preparation of the high-benzene-ring-content methacrylate monomer.

[0023] The mass ratio of the first crude product to dichloromethane is 1:8, the mass ratio of the second crude product to dichloromethane is 1:5, the first catalyst is sodium hydroxide, the second catalyst is triethylamine, the molar ratio of triethylamine to methacrylamide chloride is 1:1, and the molar ratio of sodium hydroxide to 2-chloroethanol is 1:1.

[0024] The inorganic powder is spherical silicon dioxide.

[0025] The reinforcing material was prepared by the following method: Commercial aramid fibers were shredded and added to a reactor along with anhydrous dimethyl sulfoxide. The mixture was stirred at 1000 rpm for 30 min, then potassium hydroxide was slowly added, and the stirring speed was increased to 2000 rpm for 4 h. The mixture was then stirred at 200 rpm for 7 days at room temperature to obtain a first dispersion. 2-Aminoterephthalic acid was added to the reactor containing the first dispersion, and the mixture was stirred at 100 rpm for 10 h at 60°C. After cooling to room temperature, a second dispersion was obtained. The second dispersion and the first mixture were added to a three-necked flask, which was placed in an ice-water bath at 0°C and stirred at 800 rpm. During stirring, the second solution was slowly added dropwise at 2 mL / min. The reaction was continued for 1 h while maintaining the temperature and stirring speed to obtain a gel product. The gel product was then broken into 1 cm pieces using a scraper. 3 Small pieces were added to a glass beaker with anhydrous DMF and allowed to stand for 6 hours. Then, the mixture was filtered using a Buchner funnel to retain the solid material. This process of soaking in anhydrous DMF and filtering was repeated three times to obtain the first resin. The first resin and anhydrous ethanol were then added to a glass flask and allowed to stand for 4 hours. This process of soaking in anhydrous ethanol and filtering was repeated three times to obtain the second resin. The second resin was then dried in a supercritical CO2 drying kettle to complete the preparation of the reinforcing material.

[0026] During the drying process, the supercritical CO2 drying vessel is set at 40℃ and 8MPa. First, the inlet and outlet valves are closed, and the system is kept at constant temperature and pressure for 2 hours. Then, while maintaining 40℃ and 8MPa, the outlet valve is slowly opened, and fresh supercritical CO2 is continuously pumped in for 2 hours. After that, the pressure is slowly released to atmospheric pressure within 1 hour.

[0027] The first mixed solution was prepared by mixing zinc nitrate hexahydrate, anhydrous DMF, and deionized water in a mass ratio of 1:120:6, and the second mixed solution was prepared by mixing trimesoyl chloride and anhydrous DMF in a mass ratio of 1:40.

[0028] In the preparation of the first dispersion, the mass ratio of commercial aramid fiber, anhydrous dimethyl sulfoxide, and potassium hydroxide is 1:1000:1.4, and the mass ratio of 2-aminoterephthalic acid to commercial aramid fiber is 4:1. In the washing process of the gel product, the mass ratio of the gel fragmentation product to anhydrous DMF is 1:40. In the solvent replacement process of the first adhesive, the mass ratio of the first adhesive to anhydrous ethanol is 1:35. The volume ratio of the second dispersion, the first mixed solution, and the second solution is 18:7:1.

[0029] The thermal initiator is phthalic anhydride, the reactive diluent is hydroxyethyl methacrylate, and the photoinitiator is photoinitiator TPO.

[0030] A method for preparing a high-strength, high-temperature-resistant photocurable resin for 3D printing. Step 1: Mix high-benzene-ring content methacrylate monomer, reactive diluent, and photoinitiator in a specified ratio, and mechanically stir under light-protected conditions until completely dissolved and homogeneous to obtain the first additive; mix bisphenol A epoxy resin and thermal initiator in a specified ratio, and mechanically stir until completely dissolved and homogeneous to obtain the second additive; mix the first and second additives in a specified ratio, and mechanically stir until homogeneous to obtain the resin material. Step 2: Add the resin, inorganic powder and reinforcing material together to a planetary mixer, mix at 100 r / min for 10 min, then increase the speed to 1000 r / min and mix for 30 min to obtain a slurry; Step 3: Transfer the slurry to a vacuum degassing chamber and remove bubbles under a vacuum of -0.095MPa for 15 minutes. Then discharge the slurry to complete the preparation of high-strength, high-temperature resistant photocurable resin for 3D printing.

[0031] Example 2: A high-strength, high-temperature-resistant photocurable resin for 3D printing, comprising the following parts by weight of raw materials: 50 parts resin material, 50 parts inorganic powder and 3 parts reinforcing material; The resin material is prepared by mixing the first additive and the second additive in a mass ratio of 85:15; The first additive is prepared by mixing high benzene ring content methacrylate monomer, reactive diluent and photoinitiator in a mass ratio of 50:45:3; The second additive is prepared by mixing bisphenol A type epoxy resin and thermal initiator at a mass ratio of 97:1.

[0032] The high-benzene-ring-content methacrylate monomer was prepared by the following method: tetra(4-hydroxyphenyl)methane and 2-chloroethanol were mixed in a molar ratio of 2:3, and a first catalyst was added. The mixture was reacted at 90°C for 18 h to obtain a first crude product. The first crude product was dissolved in dichloromethane and washed with 7% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The first organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding an intermediate product. The intermediate product was then mixed with methacryloyl chloride in a molar ratio of 2:3, and a second catalyst was added. The mixture was reacted at room temperature for 32 h to obtain a second crude product. The second crude product was dissolved in dichloromethane and washed with 7% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The second organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding the final product. This completed the preparation of the high-benzene-ring-content methacrylate monomer.

[0033] The mass ratio of the first crude product to dichloromethane is 1:10, the mass ratio of the second crude product to dichloromethane is 1:6, the first catalyst is sodium hydroxide, the second catalyst is triethylamine, the molar ratio of triethylamine to methacrylamide chloride is 1.2:1, and the molar ratio of sodium hydroxide to 2-chloroethanol is 1.5:1.

[0034] The inorganic powder is spherical silicon dioxide.

[0035] The reinforcing material was prepared by the following method: Commercial aramid fibers were shredded and added to a reactor along with anhydrous dimethyl sulfoxide. The mixture was stirred at 1500 rpm for 35 min, then potassium hydroxide was slowly added, and the stirring speed was increased to 2500 rpm for 5 h. The mixture was then stirred at 250 rpm for 7 days at room temperature to obtain a first dispersion. 2-Aminoterephthalic acid was added to the reactor containing the first dispersion, and the mixture was stirred at 200 rpm for 11 h at 60°C. After cooling to room temperature, a second dispersion was obtained. The second dispersion and the first mixture were added to a three-necked flask, which was placed in an ice-water bath at 3°C ​​and stirred at 900 rpm. During stirring, the second solution was slowly added dropwise at 2 mL / min. The reaction was continued for 1.1 h while maintaining the temperature and stirring speed to obtain a gel product. The gel product was then broken into 1 cm pieces using a scraper. 3 Small pieces of the mixture were added to a glass beaker with anhydrous DMF and allowed to stand for 6.5 hours. The mixture was then filtered using a Buchner funnel, retaining the solid material. This process of soaking in anhydrous DMF and filtering was repeated four times to obtain the first resin. The first resin and anhydrous ethanol were then added to a glass flask and allowed to stand for 4.5 hours. The mixture was then filtered using a Buchner funnel, retaining the solid material. This process of soaking in anhydrous ethanol and filtering was repeated four times to obtain the second resin. The second resin was then dried using a supercritical CO2 drying kettle to complete the preparation of the reinforcing material.

[0036] During the drying process, the supercritical CO2 drying vessel is set at a temperature of 40℃ and a pressure of 8MPa. First, the inlet and outlet valves are closed, and the system is kept at a constant temperature and pressure for 2.5 hours. Then, while maintaining the conditions of 40℃ and 8MPa, the system slowly opens the outlet valve and continuously pumps in fresh supercritical CO2 for 3 hours. After that, the pressure is slowly released to atmospheric pressure within 1.5 hours.

[0037] The first mixed solution was prepared by mixing zinc nitrate hexahydrate, anhydrous DMF, and deionized water in a mass ratio of 1:125:6.5, and the second mixed solution was prepared by mixing trimesoyl chloride and anhydrous DMF in a mass ratio of 1:45.

[0038] In the preparation of the first dispersion, the mass ratio of commercial aramid fiber, anhydrous dimethyl sulfoxide, and potassium hydroxide is 1:1100:1.5, and the mass ratio of 2-aminoterephthalic acid to commercial aramid fiber is 5:1. In the washing process of the gel product, the mass ratio of the gel fragmentation product to anhydrous DMF is 1:50. In the solvent replacement process of the first adhesive, the mass ratio of the first adhesive to anhydrous ethanol is 1:40. The volume ratio of the second dispersion, the first mixed solution, and the second solution is 20:8:1.

[0039] The thermal initiator is phthalic anhydride, the reactive diluent is hydroxyethyl methacrylate, and the photoinitiator is photoinitiator TPO.

[0040] A method for preparing a high-strength, high-temperature-resistant photocurable resin for 3D printing. Step 1: Mix high-benzene-ring content methacrylate monomer, reactive diluent, and photoinitiator in a specified ratio, and mechanically stir under light-protected conditions until completely dissolved and homogeneous to obtain the first additive; mix bisphenol A epoxy resin and thermal initiator in a specified ratio, and mechanically stir until completely dissolved and homogeneous to obtain the second additive; mix the first and second additives in a specified ratio, and mechanically stir until homogeneous to obtain the resin material. Step 2: Add the resin, inorganic powder and reinforcing material together to a planetary mixer, stir at 200 r / min for 11 min, then increase the speed to 1500 r / min and stir for 45 min to obtain a slurry; Step 3: Transfer the slurry to a vacuum degassing chamber and remove bubbles under a vacuum of -0.098MPa for 22 minutes. Then discharge the slurry to complete the preparation of high-strength, high-temperature resistant photocurable resin for 3D printing.

[0041] Example 3: A high-strength, high-temperature-resistant photocurable resin for 3D printing, comprising the following parts by weight of raw materials: 60 parts resin material, 60 parts inorganic powder and 5 parts reinforcing material; The resin material is prepared by mixing the first additive and the second additive in a mass ratio of 90:20; The first additive is prepared by mixing high benzene ring content methacrylate monomer, reactive diluent and photoinitiator in a mass ratio of 60:60:5; The second additive is prepared by mixing bisphenol A type epoxy resin and thermal initiator at a mass ratio of 99:1.

[0042] The high-benzene-ring content methacrylate monomer was prepared by the following method: tetra(4-hydroxyphenyl)methane and 2-chloroethanol were mixed in a molar ratio of 4.2:5, and a first catalyst was added. The mixture was reacted at 85-95℃ for 24 h to obtain a first crude product. The first crude product was dissolved in dichloromethane and washed with 10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The first organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding an intermediate product. The intermediate product was then mixed with methacryloyl chloride in a molar ratio of 4.2:4.5, and a second catalyst was added. The mixture was reacted at room temperature for 36 h to obtain a second crude product. The second crude product was dissolved in dichloromethane and washed with 10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The second organic phase was separated and distilled under reduced pressure to remove dichloromethane, yielding the final product. This completed the preparation of the high-benzene-ring content methacrylate monomer.

[0043] The mass ratio of the first crude product to dichloromethane is 1:12, the mass ratio of the second crude product to dichloromethane is 1:8, the first catalyst is sodium hydroxide, the second catalyst is triethylamine, the molar ratio of triethylamine to methacrylamide chloride is 1.5:1, and the molar ratio of sodium hydroxide to 2-chloroethanol is 2:1.

[0044] The inorganic powder is spherical silicon dioxide.

[0045] The reinforcing material was prepared by the following method: Commercial aramid fibers were shredded and added to a reactor along with anhydrous dimethyl sulfoxide. The mixture was stirred at 2000 rpm for 40 min, then potassium hydroxide was slowly added, and the stirring speed was increased to 3000 rpm for 4-6 h. Subsequently, the mixture was stirred at 300 rpm for 7 days at room temperature to obtain a first dispersion. 2-Aminoterephthalic acid was added to the reactor containing the first dispersion, and the mixture was stirred at 300 rpm for 12 h at 60°C. After cooling to room temperature, a second dispersion was obtained. The second dispersion and the first mixture were added to a three-necked flask, which was placed in an ice-water bath at 5°C and stirred at 1000 rpm. During stirring, the second solution was slowly added dropwise at 2 mL / min. The reaction was continued for 1.2 h while maintaining the temperature and stirring speed to obtain a gel product. The gel product was then broken into 1 cm pieces using a scraper. 3 Small pieces of the material were added to a glass beaker with anhydrous DMF and allowed to stand for 7 hours. Then, the mixture was filtered using a Buchner funnel to retain the solid material. This process of soaking in anhydrous DMF and filtering was repeated 5 times to obtain the first resin. The first resin and anhydrous ethanol were then added to a glass flask and allowed to stand for 5 hours. This process of soaking in anhydrous ethanol and filtering was repeated 5 times to obtain the second resin. The second resin was then dried in a supercritical CO2 drying kettle to complete the preparation of the reinforcing material.

[0046] During the drying process, the supercritical CO2 drying kettle is set at 40℃ and 8MPa. First, the inlet and outlet valves are closed, and the system is kept at constant temperature and pressure for 3 hours. Then, while maintaining 40℃ and 8MPa, the outlet valve is slowly opened, and fresh supercritical CO2 is continuously pumped in for 4 hours. After that, the pressure is slowly released to atmospheric pressure within 2 hours.

[0047] The first mixed solution was prepared by mixing zinc nitrate hexahydrate, anhydrous DMF, and deionized water in a mass ratio of 1:130:7, and the second mixed solution was prepared by mixing trimesoyl chloride and anhydrous DMF in a mass ratio of 1:50.

[0048] In the preparation of the first dispersion, the mass ratio of commercial aramid fiber, anhydrous dimethyl sulfoxide, and potassium hydroxide is 1:1200:1.6, and the mass ratio of 2-aminoterephthalic acid to commercial aramid fiber is 6:1. In the washing process of the gel product, the mass ratio of the gel fragmentation product to anhydrous DMF is 1:60. In the solvent replacement process of the first adhesive, the mass ratio of the first adhesive to anhydrous ethanol is 1:45. The volume ratio of the second dispersion, the first mixed solution, and the second solution is 22:9:1.

[0049] The thermal initiator is phthalic anhydride, the reactive diluent is hydroxyethyl methacrylate, and the photoinitiator is photoinitiator TPO.

[0050] A method for preparing a high-strength, high-temperature-resistant photocurable resin for 3D printing. Step 1: Mix high-benzene-ring content methacrylate monomer, reactive diluent and photoinitiator in proportion, and mechanically stir under light-protected conditions until completely dissolved and homogeneous to obtain the first additive; mix bisphenol A type epoxy resin and thermal initiator in proportion, and mechanically stir until completely dissolved and homogeneous to obtain the second additive; mix the first additive and the second additive in proportion, and mechanically stir until uniformly mixed to obtain the resin material; Step 2: Add the resin, inorganic powder and reinforcing material together to a planetary mixer, stir at 300 r / min for 12 min, then increase the speed to 2000 r / min and stir for 60 min to obtain a slurry; Step 3: Transfer the slurry to a vacuum degassing chamber and remove bubbles under a vacuum of -0.1 MPa for 30 minutes. Then discharge the slurry to complete the preparation of high-strength, high-temperature resistant photocurable resin for 3D printing.

[0051] Comparative Example 1: The difference between this comparative example and Example 1 is that this comparative example does not contain reinforcing material.

[0052] Comparative Example 2 differs from Example 1 in that: in the preparation of the first additive in this comparative example, an equal mass of 1,6-hexanediol diacrylate is used to replace the methacrylate monomer with a high benzene ring content.

[0053] Comparative Example 3 differs from Example 1 in that no second additive was added during the preparation of the resin material in this comparative example.

[0054] Performance testing: The photocurable resins prepared in Examples 1-3 and Comparative Examples 1-3 were tested. The photocurable resins were prepared into test pieces using a high-precision photocurable 3D printer. After being cleaned with isopropanol and post-cured in a UV lamp box for 10 minutes, they were then placed in an oven at 80°C for 1 hour for heat curing. Bending strength test: The specimen is a standard rectangular strip with dimensions of 80 mm in length, 10 mm in width, and 4 mm in thickness. At a temperature of 23±2 degrees Celsius and a relative humidity of 50±10%, the testing machine is started, and the indenter applies a load to the center of the specimen span at a constant loading speed (2 mm / min). The test continues until the specimen breaks or the deformation reaches a predetermined value. The testing system automatically records the load and deformation data throughout the process. By analyzing the load-deformation curve, it calculates and outputs the bending strength and bending modulus. The test conforms to the national standard GB / T 9341-2008 "Determination of Bending Properties of Plastics". Heat distortion: The specimen is a standard rectangular strip with dimensions of 120 mm in length, 10 mm in width, and 4 mm in thickness. A bending stress of 1.80 MPa is applied using silicone oil or other thermally stable liquid, and the temperature is strictly controlled at 120 degrees Celsius per hour. The specimen is placed in a support and a specified load is applied. The temperature of the immersion bath is increased from room temperature at a constant rate, and the bending deformation of the specimen is continuously monitored. When the maximum bending deformation of the specimen reaches 0.34 mm, the temperature in the bath at this time is recorded. This temperature is the heat distortion temperature of the specimen. Test standard: GB / T 1634.2-2019 "Determination of Load Deflection Temperature of Plastics - Part 2: Plastics and Hard Rubber"; Shore hardness: The sample thickness should be no less than 6 mm, or this thickness can be achieved through stacking. The test surface must be flat, smooth, and the upper and lower surfaces parallel. Each test point should be at least 12 mm away from the edge of the sample. Use a calibrated Shore D hardness tester, press the hardness tester vertically and smoothly against the sample surface without impact, ensuring that the indenter foot is in complete contact with the sample. According to the standard, take the reading within 1 second after the indenter foot contacts the sample, or read the instantaneous maximum value. Repeat the measurement at different positions on the sample at least 5 times, and take the median of the multiple measurements as the Shore D hardness value of the sample. Test standard: GB / T 2411-2008 "Determination of indentation hardness of plastics and hard rubber using hardness testers"; The obtained test data are recorded in Table 1 below: Table 1

[0055] By comparing and analyzing the relevant data in the table, it can be seen that the performance of the specimens prepared by the high-strength, high-temperature-resistant photocurable resins in Comparative Examples 1-3 is lower than that in Examples 1-3. Among them, Comparative Example 1 completely lacks the reinforcing material, which is the main reason for its comprehensive performance degradation. This reinforcing material is made by in-situ composite MOF with aramid fibers, which constructs a nanoscale reinforcing network in the resin matrix, which can greatly improve the load transfer efficiency and material rigidity. Without it, the resin loses the key structural support phase, resulting in a significant decrease in flexural strength, modulus, and hardness; at the same time, the loss of the inherent high thermal stability of aramid and MOF also directly reduces the heat distortion temperature of the material, making its heat resistance worse. Comparative Example 2 uses flexible aliphatic HDDA to replace the rigid methacrylate monomer with high benzene ring content, which is a fatal flaw. The large benzene ring structure can effectively restrict the movement of polymer chain segments, giving the material high rigidity, high strength and high glass transition temperature. After being replaced with flexible chain HDDA, the crosslinking network becomes compliant, the intermolecular forces weaken, resulting in a sharp drop in mechanical strength (especially flexural modulus), and the heat distortion temperature is also greatly reduced due to the easier movement of chain segments, resulting in a serious loss of temperature resistance; Comparative Example 3, without the addition of a second additive containing epoxy resin, disrupted the dual-network crosslinking structure. Epoxy resin can form interpenetrating or synergistic crosslinking networks with the acrylate system, significantly improving the overall crosslinking density and material compactness. Without the epoxy network, the material has insufficient crosslinking, and the molecular chains are more prone to relative slippage under stress, thus reducing flexural strength and modulus. Simultaneously, the excellent heat resistance of epoxy resin itself cannot contribute, resulting in a significantly lower heat distortion temperature than the complete formulation example. The photocurable resin prepared by this invention using a high-strength, high-temperature-resistant photocurable resin for 3D printing not only possesses good flexural strength and flexural modulus properties, but also excellent thermal deformation and Shore hardness. This indicates that the high-strength, high-temperature-resistant photocurable resin for 3D printing provided by this invention has a broader market prospect and is more suitable for widespread application.

[0056] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0057] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A high-strength, high-temperature-resistant photocurable resin for 3D printing, characterized in that: The raw materials include the following parts by weight: 40-60 parts resin, 40-60 parts inorganic powder, and 1-5 parts reinforcing material; The resin material is prepared by mixing the first additive and the second additive in a mass ratio of 80-90:10-20; The first additive is prepared by mixing high benzene ring content methacrylate monomer, reactive diluent and photoinitiator in a mass ratio of 40-60:30-60:1-5; The second additive is prepared by mixing bisphenol A type epoxy resin and thermal initiator at a mass ratio of 95-99:

1.

2. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 1, characterized in that, The high-benzene-ring-content methacrylate monomer is prepared by the following method: tetra(4-hydroxyphenyl)methane and 2-chloroethanol are mixed in a molar ratio of 1-4.2:1-5, and a first catalyst is added. The mixture is reacted at 85-95℃ for 12-24 h to obtain a first crude product. The first crude product is dissolved in dichloromethane and washed with 5-10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The first organic phase is separated and distilled under reduced pressure to remove dichloromethane, yielding an intermediate product. The intermediate product is then mixed with methacryloyl chloride in a molar ratio of 1-4.2:1-4.5, and a second catalyst is added. The mixture is reacted at room temperature for 28-36 h to obtain a second crude product. The second crude product is dissolved in dichloromethane and washed with 5-10% sodium hydroxide aqueous solution and saturated sodium chloride aqueous solution, respectively. The second organic phase is separated and distilled under reduced pressure to remove dichloromethane, yielding the final product, thus completing the preparation of the high-benzene-ring-content methacrylate monomer.

3. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 2, characterized in that, The mass ratio of the first crude product to dichloromethane is 1:8-12, the mass ratio of the second crude product to dichloromethane is 1:5-8, the first catalyst is sodium hydroxide, the second catalyst is triethylamine, the molar ratio of triethylamine to methacrylamide chloride is 1-1.5:1, and the molar ratio of sodium hydroxide to 2-chloroethanol is 1-2:

1.

4. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 1, characterized in that, The inorganic powder is spherical silicon dioxide.

5. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 1, characterized in that, The reinforcing material is prepared by the following method: Commercial aramid fibers are shredded and added to a reactor along with anhydrous dimethyl sulfoxide. The mixture is stirred at 1000-2000 rpm for 30-40 minutes, then potassium hydroxide is slowly added, and the stirring speed is increased to 2000-3000 rpm for 4-6 hours. Subsequently, the mixture is stirred at 200-300 rpm for 7 days at room temperature to obtain a first dispersion. 2-Aminoterephthalic acid is then added to the reactor containing the first dispersion, and the mixture is stirred at 60°C. After stirring at 100-300 rpm for 10-12 h, the mixture was cooled to room temperature to obtain a second dispersion. The second dispersion and the first mixed solution were added to a three-necked flask, which was then placed in an ice-water bath at 0-5°C. The mixture was stirred at 800-1000 rpm, with the second solution slowly added dropwise at 2 mL / min during stirring. The reaction was continued for 1-1.2 h while maintaining the temperature and stirring speed to obtain a gel product. The gel product was then broken into 1 cm pieces using a spatula. 3 Small pieces of the mixture were added to a glass beaker with anhydrous DMF and allowed to stand for 6-7 hours. Then, the mixture was filtered using a Buchner funnel to retain the solid material. This process of soaking in anhydrous DMF and filtering was repeated 3-5 times to obtain the first resin. The first resin and anhydrous ethanol were then added to a glass flask and allowed to stand for 4-5 hours. This process of soaking in anhydrous ethanol and filtering was repeated 3-5 times to obtain the second resin. The second resin was then dried in a supercritical CO2 drying kettle to complete the preparation of the reinforcing material.

6. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 5, characterized in that, During the drying process, the supercritical CO2 drying vessel is set to a temperature of 40°C and a pressure of 8MPa. First, the inlet and outlet valves are closed, and the system is kept at a constant temperature and pressure for 2-3 hours. Then, while maintaining 40°C and 8MPa, the system slowly opens the outlet valve and continuously pumps in fresh supercritical CO2 for 2-4 hours. After that, the pressure is slowly released to atmospheric pressure within 1-2 hours.

7. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 5, characterized in that, The first mixed solution is prepared by mixing zinc nitrate hexahydrate, anhydrous DMF and deionized water in a mass ratio of 1:120-130:6-7, and the second mixed solution is prepared by mixing trimesoyl chloride and anhydrous DMF in a mass ratio of 1:40-50.

8. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 5, characterized in that, In the preparation of the first dispersion, the mass ratio of commercial aramid fiber, anhydrous dimethyl sulfoxide, and potassium hydroxide is 1:1000-1200:1.4-1.6, the mass ratio of 2-aminoterephthalic acid to commercial aramid fiber is 4-6:1, the mass ratio of gel fragmentation product to anhydrous DMF in the washing process of the gel product is 1:40-60, the mass ratio of the first adhesive to anhydrous ethanol in the solvent replacement process of the first adhesive is 1:35-45, and the volume ratio of the second dispersion, the first mixed solution, and the second solution is 18-22:7-9:

1.

9. The high-strength, high-temperature-resistant photocurable resin for 3D printing according to claim 1, characterized in that, The thermal initiator is one or more of the following: hexamethylenediamine, diethylenetriamine, triethylenetetramine, maleic anhydride, phthalic anhydride, and dicyandiamide; the reactive diluent is one or more of the following: hydroxyethyl methacrylate, acrylmorpholine, N,N-dimethylacrylamide, isobornyl methacrylate, dicyclopentenyl methacrylate, and tricyclodecanediethanol diacrylate; and the photoinitiator is one or more of the following: photoinitiator 1173, TPO, TMO, and 819.

10. A method for preparing a high-strength, high-temperature-resistant photocurable resin for 3D printing according to any one of claims 1 to 9, characterized in that, Step 1: Mix the high-benzene-ring content methacrylate monomer, reactive diluent, and photoinitiator in a certain proportion, and mechanically stir under light-protected conditions until completely dissolved and homogeneous to obtain the first additive; mix the bisphenol A type epoxy resin and thermal initiator in a certain proportion, and mechanically stir until completely dissolved and homogeneous to obtain the second additive; mix the first additive and the second additive in a certain proportion, and mechanically stir until uniformly mixed to obtain the resin material; Step 2: Add the resin, inorganic powder and reinforcing material together to a planetary mixer. First, mix at 100-300 r / min for 10-12 min, then increase the speed to 1000-2000 r / min and mix for 30-60 min to obtain a slurry. Step 3: Transfer the slurry to a vacuum degassing chamber and remove bubbles for 15-30 minutes under a vacuum of -0.095MPa to -0.1MPa. Then discharge the slurry to complete the preparation of high-strength, high-temperature resistant photocurable resin for 3D printing.

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