Photocurable resin based on vegetable oil and phloroglucinol and its preparation method and application

Abstract

The application discloses a light-cured resin based on vegetable oil and phloroglucinol and a preparation method and application thereof. The light-cured resin based on vegetable oil and phloroglucinol is prepared through the following steps: S1, hydrolyzing vegetable oil to obtain vegetable oil acid; S2, mixing the vegetable oil acid, phloroglucinol, a catalyst, an additive and an organic solvent, and reacting for 1-5 hours to obtain a fatty acid phenyl ester; S3, mixing the fatty acid phenyl ester, a peroxide and an organic solvent, and reacting for 20-30 hours to obtain an epoxy fatty acid phenyl ester; S4, reacting the epoxy fatty acid phenyl ester, an acrylic compound, a catalyst and a polymerization inhibitor at 100-120 DEG C for 8-12 hours to obtain a vegetable oil-based acrylic ester prepolymer; and S5, adding dilute monomers and a photoinitiator to the vegetable oil-based acrylic ester prepolymer and stirring to obtain the light-cured resin. The light-cured resin has excellent thermal and mechanical properties, and has the advantages of fast curing speed, low penetration depth and small volume shrinkage.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to photocurable resins based on vegetable oils and phloroglucinol, their preparation methods, and applications. Background Technology

[0002] Photopolymerization technology is a green and environmentally friendly technology that uses ultraviolet light to initiate the polymerization of small organic molecules into polymer materials. Vegetable oil is a renewable and inexpensive biomass resource, widely used in coatings, inks, pesticide adjuvants, food processing, and pharmaceuticals, demonstrating good renewability and application potential. However, due to the poor uniformity of raw materials, limited and inert active sites, and high molecular chain flexibility of vegetable oils, the resulting materials often exhibit unsatisfactory performance. Traditional vegetable oil-based photocurable resins, such as epoxidized soybean oil acrylate (AESO), suffer from poor mechanical and thermal properties, making it difficult to replace traditional petroleum-based photocurable resins. Therefore, there is an urgent need to develop high-performance vegetable oil-based photocurable resins. Summary of the Invention

[0003] The purpose of this invention is to provide a photocurable resin based on vegetable oil and phloroglucinol to solve the technical problem of poor mechanical and thermal properties of existing vegetable oil-based photocurable resins.

[0004] In a first aspect, the present invention provides a photocurable resin based on vegetable oil and phloroglucinol, which is prepared by the following steps: S1. Hydrolyze vegetable oil to obtain oleic acid; S2. Mix vegetable oleic acid, phloroglucinol, catalyst, additives and organic solvent, and react for 1-5 h to obtain fatty acid phenyl esters; S3. Mix fatty acid phenyl ester, peroxide and organic solvent, and react for 20-30 h to obtain epoxy fatty acid phenyl ester; S4. React epoxy fatty acid phenyl ester, acrylic compound, catalyst and polymerization inhibitor at 100-120℃ for 8-12h to obtain vegetable oil-based acrylate prepolymer. S5. Add the diluted monomer and photoinitiator to the vegetable oil-based acrylate prepolymer, stir, and the product is obtained; The additive is N,N'-dicyclohexylcarbodiimide; the diluent monomer is acrylate.

[0005] This invention proposes a "molecular recombination" strategy to achieve structural recombination of triglycerides through core replacement. The glycerol in the triglyceride structure of vegetable oil is replaced with a rigid core, and further modification is performed to introduce an acrylic acid structure, resulting in a novel bio-based photocurable resin. The photocurable resin based on vegetable oil and phloroglucinol of this invention possesses excellent thermal and mechanical properties, fast curing speed, and low penetration depth, thus solving the technical problem of poor mechanical and thermal properties in existing vegetable oil-based photocurable resins.

[0006] In some embodiments, the vegetable oil is at least one selected from soybean oil, flaxseed oil, rapeseed oil, palm oil, sunflower seed oil, tung oil, rubber seed oil, linseed oil, and cottonseed oil.

[0007] In some embodiments, the acrylic compound is at least one of acrylic acid, methacrylic acid, butenoic acid, and sorbic acid.

[0008] In some embodiments, the catalyst is at least one of 4-dimethylaminopyridine p-toluenesulfonate (DPTS) and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and the additive is N,N'-dicyclohexylcarbodiimide (DCC).

[0009] In some embodiments, the peroxide is m-chloroperoxybenzoic acid ( m At least one of CPBA and hydrogen peroxide.

[0010] In some embodiments, the polymerization inhibitor is at least one of hydroquinone (HQ), p-hydroxyanisole, and 2,6-di-tert-butyl-p-cresol; the catalyst is at least one of triphenylphosphine (PPh3) and tetrafluoroboric acid.

[0011] In some embodiments, the diluting monomer is at least one selected from hydroxyethyl acrylate (HEA), hydroxyethyl methacrylate (HEMA), 1,6-hexanediol diacrylate (HDDA), and trimethylolpropane triacrylate (TMPTA). Preferably, the diluting monomer is hydroxyethyl methacrylate. Combining epoxidized fatty acid phenyl esters with hydroxyethyl methacrylate results in a UV-cured resin with higher tensile strength, elongation at break, and better tensile properties.

[0012] In some embodiments, in step S2, the molar ratio of phloroglucinol, oleic acid, catalyst, and additive is (0.9-1.1):(0.9-1.1):(0.9-1.1):(3.5-4.5). Preferably, the molar ratio of phloroglucinol, oleic acid, catalyst, and additive is 1:1:1:4.

[0013] In some embodiments, in step S3, the molar ratio of fatty acid phenyl ester to peroxide is 1:(4-5). Preferably, the molar ratio of fatty acid phenyl ester to peroxide is 1:4.5.

[0014] In some embodiments, in step S4, the molar ratio of phenyl epoxide fatty acid ester to polymerization inhibitor is 1:(0.05-0.09). Preferably, the molar ratio of phenyl epoxide fatty acid ester to polymerization inhibitor is 1:0.07.

[0015] In some embodiments, in step S4, the molar ratio of epoxidized fatty acid phenyl ester to catalyst is 1:(0.5-0.9). Preferably, the molar ratio of epoxidized fatty acid phenyl ester to catalyst is 1:0.5.

[0016] In some embodiments, in step S4, the molar ratio of phenyl epoxide fatty acid ester to acrylic acid compound is 1:(2.5-3.5). Preferably, the molar ratio of phenyl epoxide fatty acid ester to catalyst is 1:3.

[0017] The amount of diluent monomer used is 20%-50% of the mass of the vegetable oil-based acrylate prepolymer.

[0018] In some embodiments, the photoinitiator is selected from at least one of 2-hydroxy-2-methylphenylpropanone (PI1173) and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO).

[0019] In some embodiments, the amount of photoinitiator used is 2% of the total mass of the diluted monomer and the vegetable oil-based acrylate prepolymer.

[0020] According to a second aspect of the present invention, a method for preparing a photocurable resin based on vegetable oil and phloroglucinol is provided, comprising the following steps: S1. Mix vegetable oil, anhydrous ethanol and sodium hydroxide solution, and carry out hydrolysis reaction at 60-80℃. Adjust the pH value of the obtained product to 3-4, extract with n-hexane and retain the organic phase to obtain vegetable oleic acid. S2. Mix vegetable oleic acid, phloroglucinol, catalyst, additives and organic solvent, and react for 1-5 h to obtain fatty acid phenyl esters; S3. Mix fatty acid phenyl ester, peroxide and organic solvent, and react for 20-30 h to obtain epoxy fatty acid phenyl ester; S4. React epoxy fatty acid phenyl ester, acrylic compound, catalyst and polymerization inhibitor at 100-120℃ for 8-12h to obtain vegetable oil-based acrylate prepolymer. S5. Add the diluted monomer and photoinitiator to the vegetable oil-based acrylate prepolymer, stir, and the product is obtained; The additive is N,N'-dicyclohexylcarbodiimide; the diluent monomer is acrylate.

[0021] In some embodiments, the hydrolysis reaction temperature in step S1 is 70°C; the reaction temperature in steps S2 and S3 is 25°C.

[0022] In some embodiments, in step S1, the mass fraction of the solute in the sodium hydroxide solution is 25%.

[0023] According to a third aspect of the present invention, the application of a photocurable resin based on vegetable oil and phloroglucinol in the preparation of photocurable 3D printing materials and coatings is provided.

[0024] The photocurable resin of this invention possesses excellent mechanical and thermal properties, high carbon-carbon double bond conversion rate, low viscosity, and low penetration depth. It achieves the performance characteristics of photocurable resins used in commercial 3D printing.

[0025] The beneficial effects of this invention are as follows: (1) The light-curing resin based on vegetable oil and phloroglucinol of the present invention uses vegetable oil as raw material, which is green and environmentally friendly.

[0026] (2) The photocurable resin based on vegetable oil and phloroglucinol of the present invention has excellent thermal and mechanical properties, as well as advantages such as fast curing speed, low penetration depth and small volume shrinkage rate. It can be applied to 3D printing, coatings and other fields. Attached Figure Description

[0027] Figure 1 This is the synthetic route for the plant oil-based acrylate prepolymer of the present invention; Figure 2 The 1H NMR spectrum of soybean oleic acid triglyceride of this invention; Figure 3 The 1H NMR spectrum of the plant oil-based acrylate prepolymer of this invention; Figure 4 The graphs show the carbon-carbon double bond conversion rates of Example 1 and Comparative Example 1 of this invention. Figure 5 These are mechanical property test diagrams of the photocurable 3D printing resin samples obtained from photocurable resin materials based on vegetable oil and phloroglucinol in Examples 2-3 of the present invention. Figure 6 These are mechanical property test diagrams of the photocurable 3D printing resin samples obtained from photocurable resin materials based on vegetable oil and phloroglucinol in Examples 3-6 of this invention. Figure 7 These are mechanical property test diagrams of the photocurable 3D printing resin samples obtained from photocurable resin materials based on vegetable oil and phloroglucinol in Examples 3 and 7-9 of this invention. Figure 8These are test graphs showing the thermomechanical properties of photocurable 3D printing resin samples obtained from photocurable resin materials based on vegetable oil and phloroglucinol in Examples 3 and 7-9 of this invention. Figure 9 Viscosity test graphs of photocurable 3D printing resin samples obtained from photocurable resin materials based on vegetable oil and phloroglucinol in Examples 3 and 7-9 of this invention; Figure 10 The working curve test diagrams are for the photocurable 3D printing resin samples obtained in Example 9 and Comparative Example 2 of this invention. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto. The raw materials and reagents involved in the following embodiments are all commercially available.

[0029] This invention provides a method for preparing a photocurable resin based on vegetable oil and phloroglucinol, as follows: Figure 1 As shown. The process includes the following steps: (1) Add vegetable oil, anhydrous ethanol and 25% sodium hydroxide solution to a reactor, stir evenly and heat to 70°C for 2 h. After the reaction is complete, add phosphoric acid to adjust the pH to 3-4 and extract to obtain vegetable oleic acid; (2) Add vegetable oleic acid, phloroglucinol, catalyst, additive and dichloromethane to a reactor, stir evenly and react at 25°C for 2 h to obtain fatty acid phenyl ester; (3) Add fatty acid phenyl ester, peroxide and dichloromethane to a reactor, stir evenly and react at 25°C for 24 h to obtain epoxy fatty acid phenyl ester; (4) Add epoxy fatty acid phenyl ester, acrylic compound, catalyst and polymerization inhibitor to a reactor, stir evenly and react at 110°C for 10 h to obtain vegetable oil-based acrylate prepolymer; (5) Add diluted monomer and photoinitiator to the vegetable oil-based acrylate prepolymer, stir evenly, remove bubbles and obtain vegetable oil-based photocurable resin. (6) The obtained photocurable resin is applied to photocurable 3D printing and surface coating, and the mechanical properties, thermal properties, viscosity, penetration depth, volume shrinkage rate and other properties of the resin are tested.

[0030] It should be added that in the preparation of the vegetable oil-based acrylate prepolymer of this application, the molar ratio of soybean oil to sodium hydroxide (derived from sodium hydroxide solution) is 1:5.5, and anhydrous ethanol is used as solvent, with a general amount of 100-200 mL.

[0031] Example 1 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly, and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by extraction with n-hexane; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 2 h to obtain phenyl soybean oleate; the molar ratio of phloroglucinol and soybean oleic acid and 4-dimethylaminopyridine p-toluenesulfonate and N,N'-dicyclohexylcarbodiimide was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0032] Preparation of vegetable oil-based photocurable resin: The photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide was added to the vegetable oil-based acrylate prepolymer. The amount of photoinitiator was 2% of the total mass of the diluted monomer and the vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (TPO-PhAESO) based on vegetable oil and phloroglucinol.

[0033] The prepolymers of soybean oleate phenyl ester and vegetable oil-based acrylate were characterized by 1H NMR spectroscopy, and the results are as follows: Figure 2 and Figure 3 As shown. From Figure 2 It can be seen that there is a singlet with an integral of 3.00 at a chemical shift of 6.812 ppm, corresponding to the three hydrogen atoms on the benzene ring; there is a multiplet with an integral of 9.17 at chemical shifts of 5.32-5.39 ppm, corresponding to the hydrogen atoms on the double bonds of the three fatty acid chains; and there is a multiplet with an integral of 9.09 at chemical shifts of 9.87-0.90 ppm, corresponding to the hydrogen atoms on the methyl groups of the three fatty acid chains. This indicates that the esterification reaction of phloroglucinol and soybean oleic acid was successful, and phenyl soybean oleate was successfully obtained. Figure 3 It can be seen that there is a singlet with an integral of 3 at a chemical shift of 6.77 ppm, corresponding to the three hydrogens on the benzene ring. There are multiplets with integrals of 4.12, 4.12, and 4.14 at chemical shifts of 5.78-5.83 ppm, 6.07-6.13 ppm, and 6.32-6.43 ppm, respectively, corresponding to the three hydrogens on the double bond of the acrylate, indicating that the acrylate reaction was successful.

[0034] Comparative Example 1 This comparative example provides a plant oil-based photocurable resin material, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) After adding epoxidized soybean oil, triphenylphosphine, acrylic acid and hydroquinone to the reactor, stir evenly and heat to 120℃ for 5.5 h. After the reaction is completed, epoxidized soybean oil acrylate is obtained by extraction with n-hexane. The molar ratio of epoxidized soybean oil, acrylic acid, triphenylphosphine and hydroquinone is 1:5:0.04:0.02.

[0035] Preparation of plant oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide are added to plant oil-based acrylate prepolymer. The amount of photoinitiator is 2% of the total mass of the diluted monomer and plant oil-based acrylate prepolymer. The mixture is stirred evenly and degassed to obtain a plant oil-based photocurable resin material (TPO-AESO).

[0036] A JFUV-12B2M32 surface-source UV-LED photocuring device was used to photocur the photocurable resin materials based on vegetable oil and phloroglucinol in Example 1 and the vegetable oil-based photocurable resin material in Comparative Example 1 to obtain photocurable 3D printing resin samples. Real-time infrared spectroscopy (RT-IR) was performed on the photocurable 3D printing resin samples using a Nicolet 5700 spectrometer to obtain the carbon-carbon double bond conversion rate. The carbon-carbon double bond conversion rate was measured by detecting the 810 cm⁻¹... -1 The intensity of the C=C peak was measured. The results are shown in Table 1 and... Figure 4 As shown in Table 1, the carbon-carbon double bond conversion rate of the photocurable resin material in Example 1 after photocuring is 95%, while that in Comparative Example 1 is 81%. This indicates that the addition of PhAESO is beneficial to improving the carbon-carbon double bond conversion rate of the photocurable resin material.

[0037] Table 1. Carbon-carbon double bond conversion rate of photopolymerized 3D printing resin samples

[0038] Example 2 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly, and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by extraction with n-hexane; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol, soybean oleic acid, 4-dimethylaminopyridine p-toluenesulfonate and N,N'-dicyclohexylcarbodiimide was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0039] Preparation of vegetable oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator 2-hydroxy-2-methylphenylacetone were added to vegetable oil-based acrylate prepolymer. The amount of diluted monomer was 30% of the mass of the obtained vegetable oil-based acrylate prepolymer, and the amount of photoinitiator was 2% of the total weight of the photocurable resin. The mixture was stirred evenly and degassed to obtain a photocurable resin (PI1173-PhAESO-HEMA30) based on vegetable oil and phloroglucinol.

[0040] Example 3 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0041] Preparation of vegetable oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 30% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (TPO-PhAESO-HEMA30) based on vegetable oil and phloroglucinol.

[0042] Using a JFUV-12B2M32 surface light source type UV-LED photocuring device, PI1173-PhAESO-HEMA30 from Example 2 and TPO-PhAESO-HEMA30 from Example 3 were photocured to obtain photocured 3D printing resin samples, and their tensile properties were tested. An MTS electronic universal testing machine was used at 50 mm·min. -1 The samples were stretched at a certain rate, with each sample stretched at least 5 times, and the final result was the average value.

[0043] The tensile properties of the photopolymer 3D printing resin samples are shown in Table 2, and the mechanical properties are shown in the graphs. Figure 5As shown in Table 2, the tensile properties of the photocurable resin material in Example 3 after photocuring are significantly better than those in Example 2. This indicates that the preferred photoinitiator for the polymerization of hydroxyethyl methacrylate and PhAESO is diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide. This may be due to the fact that TPO has a maximum absorption wavelength of 380-420 nm, which provides better light absorption matching for the photocuring device used in the experiment, resulting in higher polymerization efficiency.

[0044] Table 2 Tensile properties of the photocurable 3D printing resin samples obtained in Examples 2 and 3

[0045] Example 4 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, triphenylphosphine and hydroquinone was 1:0.5:0.07.

[0046] Preparation of plant oil-based photocurable resin: Dilute monomer hydroxyethyl acrylate and photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide were added to the plant oil-based acrylate prepolymer synthesized in (1). The amount of dilute monomer was 30% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and the plant oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-HEA30) based on plant oil and phloroglucinol.

[0047] Example 5 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0048] Preparation of vegetable oil-based photocurable resin: Dilute monomer 1,6-hexanediol diacrylate and photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 30% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-HDDA30) based on vegetable oil and phloroglucinol.

[0049] Example 6 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0050] Preparation of vegetable oil-based photocurable resin: Dilute monomer trimethylolpropane triacrylate and photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 30% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-TMPTA30) based on vegetable oil and phloroglucinol.

[0051] The photocurable resins based on vegetable oil and phloroglucinol from Examples 3-6 were photocured using a JFUV-12B2M32 surface light source UV-LED photocuring device to obtain photocurable 3D printing resin samples. The tensile properties of the photocurable 3D printing resin samples were then tested. The samples were cut into 1 cm × 3 cm rectangular strips and tested using an MTS electronic universal testing machine at 50 mm / min. -1 The samples were stretched at a certain rate to test their tensile strength, elongation at break, and Young's modulus. Each sample was stretched at least 5 times, and the final result was the average value.

[0052] The tensile properties of the photocured 3D printing resin samples obtained in Examples 3-6 are shown in Table 3, and the mechanical property diagrams are shown in Figure 4. Figure 5As shown in the figure. Comparison revealed that Example 3, which combined PhAESO with hydroxyethyl methacrylate, produced a photocurable 3D printing resin sample with a tensile strength of 18.4 MPa, an elongation at break of 31.30%, and a Young's modulus of 274.56 MPa, exhibiting good tensile properties. The photocurable 3D printing resin sample obtained in Example 4 showed significantly lower tensile properties than other photocurable 3D printing resin samples, indicating that hydroxyethyl acrylate and PhAESO cannot produce a photocurable material with good tensile properties. Example 6, which combined PhAESO with trimethylolpropane triacrylate, produced a photocurable 3D printing resin sample with the highest Young's modulus (527.46 MPa) and the lowest elongation at break (4.69%). In conclusion, hydroxyethyl methacrylate is the preferred diluent monomer.

[0053] Table 3. Tensile properties of the photocurable 3D printing resin samples obtained in Examples 3-6

[0054] Example 7 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0055] Preparation of vegetable oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 20% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-HEMA20) based on vegetable oil and phloroglucinol.

[0056] Example 8 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly, and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly, and reacted at 25°C for 2 h to obtain phenyl soybean oleate. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0057] Preparation of vegetable oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 40% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-HEMA40) based on vegetable oil and phloroglucinol.

[0058] Example 9 This embodiment provides a photocurable resin material based on vegetable oil and phloroglucinol, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer: (1) Soybean oil, anhydrous ethanol and 25% sodium hydroxide solution were added to a reactor, stirred evenly and heated to 70°C for 2 h. After the reaction was completed, phosphoric acid was added to adjust the pH to 3-4, and soybean oleic acid was obtained by hexane extraction; (2) Soybean oleic acid, phloroglucinol, 4-dimethylaminopyridine p-toluenesulfonate, N,N'-dicyclohexylcarbodiimide and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 2 h to obtain phenyl soybean oleate. The molar ratio of phloroglucinol and soybean oleic acid to catalyst and additives was 1:1:1:4; (3) Soybean oleate, m-chloroperoxybenzoic acid and dichloromethane were added to a reactor, stirred evenly and reacted at 25°C for 24 h. h, epoxidized soybean oleate phenyl ester was obtained, with a molar ratio of soybean oleate phenyl ester and m-chloroperoxybenzoic acid of 1:4.5; (4) epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone were added to the reactor, stirred evenly, and reacted at 110℃ for 10 h to obtain vegetable oil-based acrylate prepolymer (PhAESO). The molar ratio of epoxidized soybean oleate phenyl ester, acrylic acid, triphenylphosphine and hydroquinone was 1:3:0.5:0.07.

[0059] Preparation of vegetable oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide were added to vegetable oil-based acrylate prepolymer. The amount of dilute monomer was 50% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and vegetable oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a photocurable resin (PhAESO-HEMA50) based on vegetable oil and phloroglucinol.

[0060] Comparative Example 2 This comparative example provides a plant oil-based UV-curable resin material, which is prepared through the following steps: Preparation of vegetable oil-based acrylate prepolymer (AESO): (1) After adding epoxidized soybean oil, triphenylphosphine, acrylic acid and hydroquinone to the reactor, stir evenly and heat to 120℃ for 5.5 h. After the reaction is completed, epoxidized soybean oil acrylate is obtained by extraction with n-hexane. The molar ratio of epoxidized soybean oil, acrylic acid, triphenylphosphine and hydroquinone is 1:5:0.04:0.02.

[0061] Preparation of plant oil-based photocurable resin: Dilute monomer hydroxyethyl methacrylate and photoinitiator diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide were added to the plant oil-based acrylate prepolymer. The amount of dilute monomer was 50% of the mass of the obtained prepolymer, and the amount of photoinitiator was 2% of the total mass of the dilute monomer and the plant oil-based acrylate prepolymer. The mixture was stirred evenly and degassed to obtain a plant oil-based photocurable resin material (AESO-HEMA50).

[0062] Using a JFUV-12B2M32 surface light source type UV-LED photocuring device, photocuring was performed on Examples 3 and 7-9 to obtain photocured 3D printing resin samples, and the following main performance indicators were tested.

[0063] Tensile properties: The samples were cut into rectangular strips of 1 cm × 3 cm and tested using an MTS electronic universal testing machine at 50 mm·min. -1 The samples were stretched at a certain rate to test their tensile strength, elongation at break, and Young's modulus. Each sample was stretched at least 5 times, and the final result was the average value.

[0064] Thermomechanical behavior: Tested using a NETZSCH DMA 242E provided by NETZSCH Scientific Instruments (Shanghai) Co., Ltd. First, the film was cut into rectangular strips of 5 mm × 15 mm, fixed on the instrument, and subjected to liquid nitrogen from -50°C at a rate of 5°C·min. -1 The temperature is increased to 150°C at a rate of 1 Hz.

[0065] Viscosity: The viscosity of the uncured liquid resin was measured using a modular intelligent advanced rheometer.

[0066] Volume shrinkage rate: tested using an MZ-A600 density meter (Shenzhen Miaozhun Scientific Instruments Co., Ltd.).

[0067] 3D printing transmission depth: Calculated using the following equation derived from Beer-Lambert's law: Z d = D p ×ln(t d / t0), where Z d , t0, t d I0 and Z represent the curing depth, critical exposure time, exposure time (resin surface), and Z, respectively. d Light intensity at =0; by plotting lnt d With Z d The working curve between them can be used to calculate D. p .

[0068] The mechanical property test results of the photocurable 3D printing resin samples obtained in each embodiment are as follows: Figure 7 As shown, the thermomechanical performance test results are as follows: Figure 8 As shown, the viscosity test results are as follows: Figure 9As shown in Table 4, the main performance indicators of different photocurable 3D printing resin samples are tested. Table 4 shows that the photocurable 3D printing resin based on vegetable oil and phloroglucinol prepared in this invention exhibits excellent thermal and mechanical properties, with Example 9 showing the best results. The photocurable material obtained in Example 9 has the best tensile strength and Young's modulus, indicating that the material is more robust and less prone to cracking and tearing. Simultaneously, it has the lowest viscosity and volume shrinkage rate, indicating that rapid 3D printing is possible and the printed objects are less likely to warp or deform.

[0069] Table 4. Main performance indicators of the photocurable 3D printing resin samples obtained in Examples 3 and 7-9

[0070] The AESO-HEMA50 of Comparative Example 2 was photocured to obtain a photocurable 3D printing resin sample. Then, the photocurable 3D printing resin samples prepared in Example 9 and Comparative Example 2 were subjected to 3D printing to determine the penetration depth, critical exposure energy, and correlation (R). 2 The results are shown in Table 5, and the working curve test graph is shown below. Figure 10 As shown in Table 5, the 3D printing resin samples prepared by this invention have lower penetration depth and critical exposure energy. This indicates that PhAESO, compared to AESO, reduces the penetration depth and critical exposure energy of the photocurable material, thus facilitating high-precision 3D printing. Furthermore, a lower critical exposure energy results in less energy loss during printing. The material exhibits lower penetration depth and volume shrinkage, promising for the creation of high-precision 3D printed crafts, molds, and other products.

[0071] Table 5. Main performance indicators of the photocurable 3D printing resin samples of Example 9 and Comparative Example 2

[0072] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A photocurable resin based on vegetable oil and phloroglucinol, characterized in that, It is prepared through the following steps: S1. Hydrolyze vegetable oil to obtain oleic acid; S2. Mix vegetable oleic acid, phloroglucinol, catalyst, additives and organic solvent, and react for 1-5 h to obtain fatty acid phenyl esters; S3. Mix fatty acid phenyl ester, peroxide and organic solvent, and react for 20-30 h to obtain epoxy fatty acid phenyl ester; S4. React epoxy fatty acid phenyl ester, acrylic compound, catalyst and polymerization inhibitor at 100-120℃ for 8-12 h to obtain vegetable oil-based acrylate prepolymer. S5. Add the diluted monomer and photoinitiator to the vegetable oil-based acrylate prepolymer and stir to obtain the final product. The additive is N,N'-dicyclohexylcarbodiimide; the diluent monomer is acrylate.

2. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, The vegetable oil is at least one of soybean oil, flaxseed oil, rapeseed oil, palm oil, sunflower seed oil, tung oil, rubber seed oil, linseed oil, and cottonseed oil; the acrylic acid compound is at least one of acrylic acid, methacrylic acid, butenoic acid, and sorbic acid; the catalyst is at least one of 4-dimethylaminopyridine p-toluenesulfonate and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride; the peroxide is at least one of m-chloroperoxybenzoic acid and hydrogen peroxide; the polymerization inhibitor is at least one of hydroquinone, p-hydroxyanisole, and 2,6-di-tert-butyl-p-cresol; the catalyst is at least one of triphenylphosphine and tetrafluoroborate; and the photoinitiator is at least one of 2-hydroxy-2-methylphenylacetone and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide.

3. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, The diluting monomer is selected from at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate.

4. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, In step S2, the molar ratio of phloroglucinol, vegetable oleic acid, catalyst and additive is (0.9-1.1):(0.9-1.1):(0.9-1.1):(3.5-4.5).

5. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, In step S3, the molar ratio of fatty acid phenyl ester to peroxide is 1:(4-5).

6. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, In step S4, the molar ratio of epoxy fatty acid phenyl ester, acrylic acid compound, polymerization inhibitor and catalyst is 1:(2.5-3.5):(0.05-0.09):(0.5-0.9).

7. The photocurable resin based on vegetable oil and phloroglucinol according to claim 1, characterized in that, The amount of diluent monomer used is 20%-50% of the mass of the vegetable oil-based acrylate prepolymer; the amount of photoinitiator used is 2% of the total mass of the diluent monomer and the vegetable oil-based acrylate prepolymer.

8. The method for preparing the photocurable resin of vegetable oil and phloroglucinol according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Mix vegetable oil, anhydrous ethanol and sodium hydroxide solution, and carry out hydrolysis reaction at 60-80℃. Adjust the pH value of the obtained product to 3-4, extract with n-hexane and retain the organic phase to obtain vegetable oleic acid. S2. Mix vegetable oleic acid, phloroglucinol, catalyst, additives and organic solvent, and react for 1-5 h to obtain fatty acid phenyl esters; S3. Mix fatty acid phenyl ester, peroxide and organic solvent, and react for 20-30 h to obtain epoxy fatty acid phenyl ester; S4. React epoxy fatty acid phenyl ester, acrylic compound, catalyst and polymerization inhibitor at 100-120℃ for 8-12 h to obtain vegetable oil-based acrylate prepolymer. S5. Add the diluted monomer and photoinitiator to the vegetable oil-based acrylate prepolymer and stir to obtain the final product. The additive is N,N'-dicyclohexylcarbodiimide; the diluent monomer is acrylate.

9. The preparation method according to claim 8, characterized in that, In step S1, the hydrolysis reaction is carried out at a temperature of 70°C; in steps S2 and S3, the reaction is carried out at a temperature of 25°C.

10. The application of the photocurable resin based on vegetable oil and phloroglucinol according to any one of claims 1 to 7 in the preparation of photocurable 3D printing materials and coatings.

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