A thermosetting fluorescent photosensitive resin for DLP-3D printing and a preparation method and application thereof

Abstract

The application discloses a thermosetting fluorescent photosensitive resin for DLP-3D printing and a preparation method and application thereof. The preparation method provided by the application is that epoxy resin is used as a prepolymer, combined with AIE fluorescent dye molecules with groups of -COOH, -OH, -SH or -NH2 through a condensation reaction, and then copolymerized with acrylic and methacrylic monomers; and then a diluent and a photoinitiator are added to prepare a novel thermosetting photosensitive resin which has fluorescence after curing. The photosensitive resin has small odor, fast curing rate and high precision of printed parts; and the parts cured under 405nm ultraviolet light can emit strong blue fluorescence under excitation of 365nm ultraviolet light.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of DLP-3D printing materials, and particularly relates to a thermosetting fluorescent photosensitive resin for DLP-3D printing and a preparation method and application thereof. BACKGROUND

[0002] 3D printing technology has produced many different types after decades of in-depth research and development. At present, the following types are more commonly used: selective laser sintering (SLS), selective laser melting (SLM), fused deposition modeling (FDM), stereo lithography (SLA and DLP), and poly jet technology. Among them, DLP stereo lithography is a widely researched, mature and commonly used rapid prototyping method in the world. DLP printing uses photosensitive resin as the material, which is prepared by low polymer, diluent, photoinitiator and various additives according to a certain experimental ratio. The photosensitive resin is cured by polymerization under specific wavelength light to achieve the purpose of solidification. The curing process is to project the liquid photosensitive resin layer by layer after the completion of the solidification of one face, and finally to manufacture a three-dimensional entity.

[0003] In recent years, due to the popularity of DLP-3D printing technology and photosensitive resin, people have been unable to satisfy only designing and printing various three-dimensional models. A variety of printing materials have appeared in recent years, such as 4D printing materials, which will change in shape under the stimulation of light and heat. Human demand for multifunctional printing materials is increasing day by day.

[0004] Chinese patent applications with publication numbers CN115057708B, CN113045708B, CN112812623B, CN111171251B and CN111205467B all disclose 3D printing materials with fluorescent effect. However, the above-mentioned several disclosed technologies are based on traditional fluorescent dyes, which have the disadvantages of easy quenching and easy bleaching, hindering their possible practical application.

[0005] Therefore, the present application is proposed. SUMMARY

[0006] In view of the shortcomings of the existing commercial photosensitive resin, the purpose of the present application is to provide a preparation method of thermosetting fluorescent photosensitive resin for DLP-3D printing. The thermosetting fluorescent photosensitive resin prepared by the method not only has small irritating odor, fast curing speed and high printing precision, but also can emit strong blue fluorescence under 365nm ultraviolet excitation, and the fluorescence is not easy to quench or bleach.

[0007] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0008] The preparation method of thermosetting fluorescent photosensitive resin for DLP-3D printing provided by the present application is to graft AIE fluorescent dye molecules on the epoxy resin as prepolymer through condensation reaction, and then copolymerize with acrylic monomer; and then add diluent and photoinitiator to prepare the thermosetting fluorescent photosensitive resin for DLP-3D printing.

[0009] The specific preparation method includes the following steps:

[0010] (1) mixing AIE fluorescent dye molecules and epoxy resin prepolymer and then refluxing to obtain reaction system 1;

[0011] (2) dissolving triphenylphosphine in acrylic monomer and adding it into the reaction system 1 for continuous refluxing;

[0012] (3) moving the product obtained in step (2) to room temperature, adding photoinitiator and diluent thereto, and reacting at room temperature to obtain the thermosetting fluorescent photosensitive resin for DLP-3D printing.

[0013] In the above method step (1), the AIE fluorescent dye molecule has at least one active group capable of ring-opening reaction with epoxy group, including but not limited to: carboxyl group, hydroxyl group, mercapto group or amino group;

[0014] Further, the AIE fluorescent dye molecule can be a tetraphenyl ethylene (TPE) fluorescent molecule; according to the embodiment of the present application, the AIE fluorescent dye molecule is TPE-COOH (Macrolin, CAS No.: 197153-87-0).

[0015] In the above method step (1), the epoxy resin prepolymer includes but is not limited to: bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin or phenolic epoxy resin and the like common reagents.

[0016] According to the embodiment of the present application, the epoxy resin prepolymer is bisphenol A epoxy resin (Macrolin, CAS No.: 30583-72-3).

[0017] In the step (1) of the method, the AIE fluorescent dye molecule is TPE-COOH with a single carboxyl group, and the mass ratio of the TPE-COOH to the epoxy resin prepolymer is (0.01-0.05) g:(80-100) g.

[0018] According to an embodiment of the present application, the mass ratio of the TPE-COOH to the bisphenol A epoxy resin can be 0.01:80, 0.03:80, 0.05:80 or 0.01:100.

[0019] In the step (1) of the method, the reaction condition of the reflux reaction is reflux stirring at 80-85°C for 1-2h, for example, reflux stirring at 80°C for 1h. The stirring rate can be 250r / min.

[0020] In the step (2) of the method, the acrylic monomer includes but is not limited to acrylic and methacrylic monomers. According to an embodiment of the present application, the acrylic monomer is methacrylic acid.

[0021] In the step (2) of the method, the mass ratio of the triphenylphosphine to the methacrylic acid is (0.72-1.44) g:(40-60) g.

[0022] According to an embodiment of the present application, the mass ratio of the triphenylphosphine to the methacrylic acid is 0.72g:40g, 0.72g:50g or 0.72g:60g.

[0023] According to an embodiment of the present application, the triphenylphosphine is dissolved in the methacrylic acid, and the reaction system 1 is dripped with the triphenylphosphine in 1-1.5h.

[0024] In the step (2) of the method, the reaction condition of the reflux reaction is reflux stirring at 100-110°C for 4-5h, for example, reflux stirring at 100°C for 4h. The stirring rate is 350r / min.

[0025] In the step (3) of the method, the photoinitiator is a long-wave photoinitiator, including but not limited to 2-dimethylamino-2-benzyl-1-[4-(4-morpholinyl)phenyl]-1-butanone (910), 2,4,6(trimethylbenzoyl)diphenyl phosphine oxide (TPO), 2,4,6-trimethylbenzoyl phosphonic acid ethyl ester (TPO-L), 2 isopropyl thioxanthone (2,4 isomer mixture) (ITX) and other common long-wave photoinitiators.

[0026] In the step (3) of the method, the diluent includes but is not limited to isopropyl alcohol acrylate, ethoxy ethoxy ethyl acrylate, neopentyl glycol diacrylate.

[0027] According to an embodiment of the present application, the photoinitiator is 2-dimethylamino-2-benzyl-1-[4-(4-morpholinyl)phenyl]-1-butanone (910), and the diluent is ethoxyethoxyethyl acrylate.

[0028] The feeding ratio of the photoinitiator 910 and the diluent ethoxyethoxyethyl acrylate is (4-8) g:(40-60) g;

[0029] In the above method step (3), the reaction is continuously stirred at room temperature for 1-2 h, specifically for 1 h. The stirring rate is 80 r / min.

[0030] In the present application, the feeding ratio of the raw material TPE-COOH, the epoxy resin prepolymer (such as bisphenol A epoxy resin), triphenylphosphine, methacrylic acid, the photoinitiator (such as photoinitiator 910), and the diluent ethoxyethoxyethyl acrylate is (0.01-0.05) g:(80-100) g:(0.72-0.144) g:(40-60) g:(4-8) g:(40-60) g.

[0031] Preferably, in step (1), the amount of TPE-COOH is 0.01 g, the amount of bisphenol A epoxy resin is 80 g, and the stirring rate is 250 r / min.

[0032] Preferably, in step (2), the amount of triphenylphosphine is 0.72 g, the amount of methacrylic acid is 40 g, and the reflux stirring condition is 100℃, 350 r / min stirring for 4 h.

[0033] Preferably, in step (3), the amount of photoinitiator 910 is 4 g, the amount of diluent ethoxyethoxyethyl acrylate is 40 g, and the stirring condition is 80 r / min stirring at room temperature for 1 h.

[0034] The present application aims to provide a preparation method of 3D printing AIE fluorescent resin. Different types of epoxy resins, AIE dye molecules, monomers, diluents, and photoinitiators are within the protection scope of the present application.

[0035] The thermosetting fluorescent photosensitive resin for DLP-3D printing prepared by the above method is also within the protection scope of the present application.

[0036] The present application also provides the application of the above-mentioned thermosetting fluorescent photosensitive resin for DLP-3D printing.

[0037] The application is the application of the thermosetting fluorescent photosensitive resin for DLP-3D printing in the preparation of at least one product.

[0038] The application also provides a DLP-3D printing resin product.

[0039] The DLP-3D printing resin product is prepared by the method comprising the following steps: 3D printing by using the thermosetting fluorescent photosensitive resin through a DLP-3D printing method.

[0040] The application designs a new type of DLP-3D thermosetting photosensitive resin which does not emit fluorescence in a liquid state and emits fluorescence after curing by combining the characteristics of the Aggregation-induced Emission (AIE) molecule emitting fluorescence under motion restriction with the photosensitive resin. The photosensitive resin not only has small irritating odor, fast curing speed and high printing precision, but also emits strong fluorescence under the excitation of 365nm ultraviolet after curing. The fluorescence is not easy to be quenched or bleached. Even three primary color AIE molecules combined with the photosensitive resin can be designed to print colorful printing models by adjusting the mixing ratio of the photosensitive resin, so that the printing process is more interesting.

[0041] After the technical scheme is adopted, the preparation method of the thermosetting fluorescent photosensitive resin for DLP-3D printing has the following advantages. In step (1), the carboxyl group of TPE-COOH is first used to react with bisphenol A epoxy resin to generate ring-opening polymerization. The synthesis process is simple, the AIE fluorescent molecule and bisphenol A epoxy resin are widely available, the production cost is low, the operation is simple, and the production can be easily expanded. The AIE molecule TPE-COOH emits weak fluorescence or even no fluorescence in a monodisperse state. However, when the motion of the benzene ring on the molecule is restricted, the fluorescence intensity of the molecule will be greatly enhanced. This phenomenon is completely opposite to the quenching (ACQ) effect of traditional dyes. Based on the characteristic that the TPE-COOH molecule emits fluorescence under motion restriction, the molecule is designed to be crosslinked with bisphenol A epoxy resin by condensation. In step (2), triphenylphosphine is dissolved in methacrylic acid and then polymerized with bisphenol A epoxy resin. Triphenylphosphine is a common reagent, which is easy to obtain, low in cost and easy to expand production. In addition, compared with acrylic acid, methacrylic acid can alleviate the yellowing of the finished product to a certain extent. In step (3), 910 is used as a photoinitiator, and ethoxyethoxyethyl acrylate is used as a diluent. Compared with other photoinitiators, the absorption wavelength is relatively wide, and the yellowing of the finished product is alleviated to a certain extent.

[0042] Therefore, the new type of DLP-3D thermosetting photosensitive resin prepared by the method not only has small irritating odor, fast curing speed and high printing precision, but also emits strong fluorescence under the excitation of 365nm ultraviolet after curing. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 The raw material prepared in Example 8 was used to print a model by DLP-3D printing, and the fluorescence emitted by the model under excitation at 365 nm was observed. DETAILED DESCRIPTION

[0044] The application will be further described in conjunction with the specific embodiments. The examples provided below are only for the purpose of illustrating the application, and are not intended to limit the scope of the application. The examples provided below can serve as a guide for further improvement by those skilled in the art, and do not in any way constitute a limitation on the application.

[0045] In the following examples, the experimental methods are conventional methods, and are performed according to the techniques or conditions described in the literature in the art or according to the product instructions, unless otherwise specified. The materials, reagents, etc. used in the following examples can be obtained commercially, unless otherwise specified.

[0046] In the following examples, bisphenol A epoxy resin (McMaster, CAS No. 30583-72-3), TPE-COOH (McMaster, CAS No. 197153-87-0), diluent ethoxyethoxyethyl acrylate (McMaster, CAS No. 7328-17-8), and photoinitiator 910 (McMaster, CAS No. 119313-12-1) were selected as the research objects, and the preparation method of the thermosetting fluorescent photosensitive resin for DLP-3D printing was specifically introduced.

[0047] In the following examples, the "good, medium, poor" standard of the molding degree is based on a 5x5 array of 1 μm x 1 μm x 1 μm cubes. All the cubes printed at a molding rate of 100% are good; those with a molding rate of 60% or more are medium; and those with a molding rate of less than 60% are poor.

[0048] Example One

[0049] (1) 0.01 g of monocarboxyl TPE-COOH (4-(1,2,2-triphenylvinyl) benzoic acid) was added to 80 g of bisphenol A epoxy resin and transferred to a 250 g flask, and the material was refluxed and stirred (250 r / min) at 80°C for 1 h.

[0050] (2) 0.72 g of triphenylphosphine was dissolved in 40 g of methyl methacrylate, and was added dropwise to the flask within 1 h and continued to be refluxed and stirred at 100°C at 350 r / min for 4 h.

[0051] (3) Then the product obtained in step (2) is moved to room temperature, 4g of photoinitiator 910 and 40g of diluent ethoxyethoxyethyl acrylate are added to the flask, and stirring is continued at room temperature at 80r / min for 1h to obtain a thermosetting fluorescent photosensitive resin.

[0052] The thermosetting fluorescent photosensitive resin obtained above is subjected to DLP-3D printing (model: Longer Orange 10) to obtain a printed model finished product.

[0053] The tensile stress of the fluorescent photosensitive resin is tested to be 25MPa, and the 3D printing forming degree is good.

[0054] Example Two

[0055] (1) 0.03g of TPE-COOH with a single carboxyl group is added to 80g of bisphenol A epoxy resin and then transferred to a 250mL flask, and the reaction is refluxed at 80℃ with stirring at 250r / min for 1h.

[0056] (2) 0.72g of triphenylphosphine is dissolved in 40g of methacrylic acid, which is added dropwise into the flask within 1h and continues to be refluxed at 100℃ with stirring at 350r / min for 4h.

[0057] (3) Then the product obtained in step (2) is moved to room temperature, 4g of photoinitiator 910 and 40g of diluent ethoxyethoxyethyl acrylate are added to the flask, and stirring is continued at room temperature at 80r / min for 1h.

[0058] The thermosetting fluorescent photosensitive resin obtained above is subjected to DLP-3D printing, and a printed model finished product is obtained.

[0059] The tensile stress of the fluorescent photosensitive resin is tested to be 30MPa, and the 3D printing forming degree is good.

[0060] Example Three

[0061] (1) 0.05g of TPE-COOH with a single carboxyl group is added to 80g of bisphenol A epoxy resin and then transferred to a 250mL flask, and the reaction is refluxed at 80℃ with stirring at 250r / min for 1h.

[0062] (2) 0.72g of triphenylphosphine is dissolved in 40g of methacrylic acid, which is added dropwise into the flask within 1h and continues to be refluxed at 100℃ with stirring at 350r / min for 4h.

[0063] (3) Then the product obtained in step (2) is moved to room temperature, 4g of photoinitiator 910 and 40g of diluent ethoxyethoxyethyl acrylate are added to the flask, and stirring is continued at room temperature at 80r / min for 1h.

[0064] The thermosetting fluorescent photosensitive resin obtained above is subjected to DLP-3D printing to obtain a printed model finished product.

[0065] The tensile stress of the fluorescent photosensitive resin is tested to be 42 MPa, and the 3D printing forming degree is good.

[0066] Example Four

[0067] (1) 0.01 g of TPE-COOH with a single carboxyl group is added to 100 g of bisphenol A epoxy resin, then transferred to a 250 mL flask, and the reaction is refluxed at 80°C with stirring at 250 r / min for 1 h.

[0068] (2) 0.72 g of triphenylphosphine is dissolved in 40 g of methacrylic acid, added dropwise into the flask within 1 h, and continuously refluxed at 100°C with stirring at 350 r / min for 4 h.

[0069] (3) Then the product obtained in step (2) is moved to room temperature, 4 g of a photoinitiator 910 and 40 g of a diluent ethoxyethoxyethyl acrylate are added to the flask, and continuously stirred at 80 r / min at room temperature for 1 h.

[0070] The thermosetting fluorescent photosensitive resin obtained above is subjected to DLP-3D printing to obtain a printed model finished product.

[0071] The tensile stress of the fluorescent photosensitive resin is tested to be 26 MPa, and the 3D printing forming degree is medium.

[0072] Example Five

[0073] (1) 0.01 g of TPE-COOH with a single carboxyl group is added to 80 g of bisphenol A epoxy resin, then transferred to a 250 mL flask, and the reaction is refluxed at 80°C with stirring at 250 r / min for 1 h.

[0074] (2) 0.72 g of triphenylphosphine is dissolved in 50 g of methacrylic acid, added dropwise into the flask within 1 h, and continuously refluxed at 100°C with stirring at 350 r / min for 4 h.

[0075] (3) Then the product obtained in step (2) is moved to room temperature, 4 g of a photoinitiator 910 and 40 g of a diluent ethoxyethoxyethyl acrylate are added to the flask, and continuously stirred at 80 r / min at room temperature for 1 h.

[0076] The thermosetting fluorescent photosensitive resin obtained above is subjected to DLP-3D printing to obtain a printed model finished product.

[0077] The tensile stress of the fluorescent photosensitive resin is tested to be 25 MPa, and the 3D printing forming degree is good.

[0078] Example Six

[0079] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol F epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0080] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, which was added dropwise to the flask within 1 h and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0081] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 40 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0082] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished printing model.

[0083] The tensile stress of the above fluorescent photosensitive resin was tested to be 23 MPa, and the 3D printing degree was good.

[0084] Example Seven

[0085] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol A epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0086] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, which was added dropwise to the flask within 1 h and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0087] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 40 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0088] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished printing model.

[0089] The tensile stress of the above fluorescent photosensitive resin was tested to be 25 MPa, and the 3D printing degree was good.

[0090] Example Eight

[0091] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol F epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0092] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, which was added dropwise to the flask within 1 h and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0093] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 40 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0094] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished product of the printed model.

[0095] The tensile stress of the above fluorescent photosensitive resin was tested to be 26 MPa, and the 3D printing forming degree was good.

[0096] The raw material prepared in this embodiment 8 was used for DLP-3D printing, and the model emitted very strong fluorescence under 365 nm excitation. The results are shown in Figure 1 .

[0097] Example Nine

[0098] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol F epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0099] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, which was added dropwise to the flask within 1 h and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0100] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 40 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0101] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished product of the printed model.

[0102] The tensile stress of the above fluorescent photosensitive resin was tested to be 26 MPa, and the 3D printing forming degree was good.

[0103] Example Ten

[0104] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol A epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0105] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, added dropwise to the flask within 1 h, and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0106] (3) Then the product obtained in step (2) was moved to room temperature, 8 g of photoinitiator 910 and 40 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0107] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished printing model.

[0108] The tensile stress of the above fluorescent photosensitive resin was tested to be 24 MPa, and the 3D printing forming degree was good.

[0109] Example Eleven

[0110] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol A epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0111] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, added dropwise to the flask within 1 h, and continued to be refluxed at 100°C with stirring at 350 r / min for 4 h.

[0112] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 50 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0113] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a finished printing model.

[0114] The tensile stress of the above fluorescent photosensitive resin was tested to be 20 MPa, and the 3D printing forming degree was medium.

[0115] Example Twelve

[0116] (1) 0.01 g of TPE-COOH with a single carboxyl group was added to 80 g of bisphenol A epoxy resin and transferred to a 250 mL flask, and the reaction was refluxed at 80°C with stirring at 250 r / min for 1 h.

[0117] (2) 0.72 g of triphenylphosphine was dissolved in 60 g of methacrylic acid, which was dropped into the flask within 1 h and continued to be stirred at 100°C at 350 r / min for 4 h.

[0118] (3) Then the product obtained in step (2) was moved to room temperature, 4 g of photoinitiator 910 and 60 g of diluent ethoxyethoxyethyl acrylate were added to the flask, and stirring was continued at room temperature at 80 r / min for 1 h.

[0119] The thermosetting fluorescent photosensitive resin obtained above was subjected to DLP-3D printing to obtain a printed model product.

[0120] The tensile stress of the fluorescent photosensitive resin above was tested to be 18 MPa, and the 3D printing degree was high.

[0121] Table 1

[0122] The present application has been described in detail. For those skilled in the art, without departing from the purpose and scope of the present application, and without unnecessary experiments, the present application can be implemented in a wider range under the same parameters, concentrations and conditions. Although the present application gives a special example, it should be understood that the present application can be further improved. In summary, according to the principle of the present application, the present application intends to include any change, use or improvement of the present application, including changes made by conventional techniques known in the art, which deviates from the scope disclosed in the present application. Some basic features can be applied within the scope of the following attached claims.

Claims

1. A method for preparing a thermosetting fluorescent photosensitive resin for DLP-3D printing, comprising using epoxy resin as a prepolymer, grafting AIE fluorescent dye molecules onto it through a ring-opening polymerization reaction, and then copolymerizing it with acrylic monomers; and then adding a diluent and a photoinitiator to obtain the thermosetting fluorescent photosensitive resin for DLP-3D printing. The method includes the following steps: (1) AIE fluorescent dye molecules were mixed with epoxy resin prepolymer and then subjected to reflux reaction to obtain reaction system 1; (2) Dissolve triphenylphosphine in an acrylic monomer and add it to the reaction system 1 and continue the reflux reaction; (3) The product obtained in step (2) is placed at room temperature, and a photoinitiator and a diluent are added thereto. The reaction is carried out at room temperature to obtain the thermosetting fluorescent photosensitive resin for DLP-3D printing. The AIE fluorescent dye molecule has at least one active group that can undergo a ring-opening reaction with an epoxy group, including but not limited to: having a carboxyl group, a hydroxyl group, a thiol group or an amino group; The epoxy resin prepolymers include, but are not limited to: bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin or phenolic epoxy resin. The acrylic monomers include, but are not limited to: acrylic and methacrylic monomers; In step (3), the photoinitiator is a long-wavelength photoinitiator, including but not limited to: 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone (910), 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide (TPO), ethyl 2,4,6-trimethylbenzoylphosphonate (TPO-L), and 2-isopropylthioanthrone (ITX); In step (3), the diluent includes, but is not limited to: isopropanol acrylate, ethoxyethoxyethyl acrylate, and neopentyl glycol diacrylate; In step (1), the reaction conditions for the reflux reaction are: reflux and stirring at 80~85℃ for 1~2 h; In step (2), the reaction conditions for the reflux reaction are: reflux stirring at 100~110℃ for 4~5 h.

2. The preparation method according to claim 1, characterized in that: The AIE fluorescent dye molecule is a tetraphenylethylene (TPE) fluorescent molecule.

3. The preparation method according to claim 2, characterized in that: In step (1), the AIE fluorescent dye molecule is a monocarboxyl TPE-COOH, and the mass ratio of the monocarboxyl TPE-COOH to the epoxy resin prepolymer is (0.01~0.05) g: (80~100) g. And / or, in step (2), the acrylic monomer is methacrylic acid, and the feeding ratio of triphenylphosphine to methacrylic acid is (0.72~1.44) g: (40~60) g.

4. The preparation method according to claim 1, characterized in that: In step (3), the reaction is carried out under continuous stirring at room temperature for 1-2 hours.

5. The preparation method according to claim 1, characterized in that: In step (3), the photoinitiator is 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone (910), the diluent is ethoxyethoxyethyl acrylate, and the feeding ratio of the photoinitiator 910 and ethoxyethoxyethyl acrylate is (4-8) g: (40~60) g.

6. The thermosetting fluorescent photosensitive resin for DLP-3D printing prepared by the method of any one of claims 1-5.

7. A DLP-3D printed resin product, characterized in that: The DLP-3D printed resin article is prepared by a method comprising the following steps: using a thermosetting fluorescent photosensitive resin for DLP-3D printing prepared by any one of claims 1-5, 3D printing is performed by the DLP-3D printing method to obtain the product.

Images