A bio-based self-sensitized acrylate monomer, a bio-based photocured film and a preparation method thereof

Abstract

The application discloses a kind of bio-based self-photosensitive acrylate monomer, bio-based photocured film and preparation method thereof, the structural formula of the bio-based self-photosensitive acrylate monomer is, wherein it indicates the residue after the hydroxyl of sucrose is removed, X, Y is independently the residue after the acryloyloxy of multifunctional acrylate monomer is removed, n takes 1~8 between the positive integer.The quaternary carbon structure in the bio-based self-photosensitive acrylate monomer has self-photosensitive function, and the use amount of photoinitiator can be reduced when photocuring, and the obtained photocured film has good hardness and adhesion.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, and particularly relates to a bio-based self-photosensitive acrylate monomer, a bio-based photocurable film, and a method for preparing the same. Background Technology

[0002] With the severe shortage of petroleum resources and the increasing severity of environmental pollution, people are paying more and more attention to resource utilization and environmental protection. Photopolymerization technology, with its advantages of fast polymerization reaction speed, adaptability to light, energy saving and environmental protection, high production efficiency, excellent curing performance, safety and low pollution, is hailed as a new generation of environmentally friendly technology. Since the beginning of the 21st century, the photopolymerization industry has developed rapidly, and its applications have spread to various fields of production and daily life. The scarcity and non-renewable nature of petroleum resources have made the research and development of bio-based polymer materials a focus of attention. Developing and utilizing bio-based materials, and obtaining raw materials for coatings, inks, and adhesives that are less dependent on petroleum resources through appropriate chemical modification, will become a research hotspot in the field of polymer materials.

[0003] Sucrose, a non-reducing disaccharide formed by the condensation of glucose and fructose through α,β-1,2-glycosidic bonds, is widely found in sugarcane, sugar beets, and various plant tissues. Sucrose possesses excellent water solubility, sweetness, and biocompatibility, and is abundant, renewable, and environmentally friendly, thus finding wide application in food, pharmaceutical, chemical, and materials industries. In addition to its use as a conventional sweetener, the sucrose molecule contains eight active hydroxyl groups, offering excellent potential for chemical modification. Different functional groups can be introduced through esterification, etherification, and acetalization to prepare a variety of functional sucrose derivatives. These derivatives exhibit superior performance in biodegradable plastics, medical adhesives, drug delivery systems, bio-based coatings, and electronic packaging materials, providing an important raw material foundation for the construction of bio-based polymer materials. Furthermore, the unique spatial configuration and multi-reactive-site characteristics of the sucrose molecule offer new ideas and pathways for the design and construction of multi-scale functional materials.

[0004] Therefore, sucrose is not only a traditional food additive, but also a highly promising bio-based compound. Its development and application are of great significance for expanding research on green chemistry and high-performance bio-based materials. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the present invention provides a bio-based self-photosensitive acrylate monomer, a bio-based photocurable film, and a method for preparing the same.

[0006] The purpose of this invention is to provide a bio-based self-photosensitive acrylate monomer having a structure as shown in formula (I):

[0007] Equation (Ⅰ);

[0008] in, This refers to the residues remaining after the hydroxyl groups are removed from sucrose;

[0009] X and Y are residues of polyfunctional acrylate monomers after removing one acryloyl group;

[0010] n is a positive integer between 1 and 8.

[0011] In some embodiments of the present invention, the bio-based photosensitive acrylate monomer is obtained by reacting a beta-dicarbonyl compound with the polyfunctional acrylate monomer, and the structure of the beta-dicarbonyl compound is shown in formula (II):

[0012] Formula (II).

[0013] In some embodiments of the present invention, the raw materials for preparing the beta-dicarbonyl compound include diketene and sucrose.

[0014] In some embodiments of the present invention, the polyfunctional acrylate monomer is selected from at least one of 1,6-hexanediol di(meth)acrylate, tripropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol, and trimethylolpropane tri(meth)acrylate.

[0015] A second objective of this invention is to provide a method for preparing the above-mentioned bio-based self-sensitive acrylate monomer, comprising the following steps:

[0016] The beta-dicarbonyl compound was mixed with a multifunctional acrylate monomer, a second catalyst, and a second solvent, reacted, and purified to obtain the bio-based self-sensitive acrylate monomer.

[0017] In some embodiments of the present invention, the molar ratio of the beta-dicarbonyl compound, the polyfunctional acrylate monomer, and the second catalyst is 1:2~16:0.15~0.60.

[0018] In some embodiments of the present invention, the temperature of the second reaction is 80~100°C.

[0019] In some embodiments of the present invention, the second reaction takes 10 to 12 hours.

[0020] In some embodiments of the present invention, the second catalyst is selected from 1,8-diazabicyclo[5.4.0]undec-7-ene.

[0021] In some embodiments of the present invention, the second solvent is selected from N,N-dimethylformamide.

[0022] In some embodiments of the present invention, the preparation step of the beta-dicarbonyl-containing compound includes: mixing diketene, sucrose, a first catalyst, and a first solvent, carrying out a first reaction, and purifying to obtain the beta-dicarbonyl-containing compound. The reaction formula is as follows:

[0023]

[0024] In some embodiments of the present invention, the molar ratio of diketene, sucrose, and the first catalyst is 1~8:1:0.075~0.3.

[0025] In some embodiments of the present invention, the temperature of the first reaction is 20~40°C.

[0026] In some embodiments of the present invention, the time for the first reaction is 8 to 12 hours.

[0027] In some embodiments of the present invention, the first catalyst is selected from 4-dimethylaminopyridine.

[0028] In some embodiments of the present invention, the first solvent is selected from N,N-dimethylformamide.

[0029] The synthetic route of the bio-based self-photosensitive acrylate monomer of the present invention is as follows: sucrose and diketene react under the action of a catalyst to generate an intermediate containing a beta-dicarbonyl compound, and the intermediate containing the beta-dicarbonyl compound undergoes Michael addition with one of the acryloxy groups of the polyfunctional acrylate monomer to obtain the bio-based self-photosensitive acrylate monomer.

[0030] A third objective of this invention is to provide a bio-based photocurable film, the raw materials of which include the above-mentioned bio-based self-photosensitive acrylate monomer, or the bio-based self-photosensitive acrylate monomer prepared by the above-mentioned preparation method.

[0031] In some embodiments of the present invention, the raw materials for preparation further include a free radical photoinitiator and an active diluent.

[0032] In some embodiments of the present invention, the free radical photoinitiator is selected from at least one of (2,4,6-trimethylbenzoyl)diphenylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, and 2-hydroxy-2-methyl-1-phenyl-1-propanone.

[0033] In some embodiments of the present invention, the active diluent is at least one of epoxidized soybean oil acrylate and tetrahydrofuran acrylate.

[0034] In some embodiments of the present invention, the raw materials for preparation include, by weight, the bio-based self-sensing acrylate monomer, the free radical photoinitiator, and the reactive diluent in a mass ratio of 1:0.1~0.40:0.02~0.08.

[0035] The fourth objective of this invention is to provide a method for preparing the above-mentioned bio-based photocurable film, comprising the following steps: mixing all the raw materials evenly, coating the film, and performing a photocuring reaction to obtain the bio-based photocurable film.

[0036] In some embodiments of the present invention, the temperature of the photocuring reaction is 40~100℃.

[0037] In some embodiments of the present invention, the photocuring reaction time is 0.5 to 15 minutes.

[0038] In some embodiments of the present invention, the light intensity of the photocuring reaction is 30~40 mw / cm. 2 .

[0039] The bio-based photocurable film of the present invention can be applied in the fields of food, cosmetics, medicine, and industry.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] First, this invention synthesizes a beta-dicarbonyl compound by reacting highly reactive diketene with sucrose containing a strong nucleophilic hydroxyl group under specific catalytic conditions. This step is mild, and the chemical modification of the environmentally friendly bio-based material sucrose significantly reduces the application of petroleum-based polymers. Second, the beta-dicarbonyl compound is reacted with a multifunctional acrylate monomer via a Michael addition reaction to form a bio-based self-photosensitive acrylate monomer. The quaternary geminal carbon structure in this bio-based self-photosensitive acrylate monomer has the function of photosensitive decomposition to generate active free radicals. Under ultraviolet light irradiation, it can initiate the polymerization of acrylate double bonds, directly crosslinking and curing into a film. Therefore, the film-forming process of this invention can greatly reduce the amount of photoinitiator used, thus avoiding the hazards caused by the large amount of photoinitiator used in traditional photocuring technology. Furthermore, the resulting photocured film has good hardness and adhesion. In addition, the introduction of sucrose is of great significance for expanding research on green chemistry and high-performance bio-based materials. Attached Figure Description

[0042] Figure 1 The appearance morphology of the bio-based photocurable film S-1 in Example 7 is shown.

[0043] Figure 2 The appearance morphology of the bio-based photocurable film S-2 in Example 8 is shown.

[0044] Figure 3 The appearance morphology of the bio-based photocurable film S-3 in Example 9 is shown.

[0045] Figure 4 The appearance morphology of the bio-based photocurable film S-4 in Example 10 is shown.

[0046] Figure 5 The appearance morphology of the bio-based photocurable film S-5 in Example 11 is shown.

[0047] Figure 6 The appearance morphology of the bio-based photocurable film S-6 in Example 12 is shown.

[0048] Figure 7 The UV absorption spectra of the bio-based self-sensing acrylate monomers obtained in Examples 1-6 are shown.

[0049] Figure 8 The infrared spectra of the bio-based self-photosensitive acrylate monomers obtained in Examples 1-6 are shown.

[0050] Figure 9 The infrared spectra of the bio-based photocurable films S-1 to S-6 obtained in Examples 7 to 12 are shown.

[0051] Figure 10 The thermogravimetric analysis (TGA) results for bio-based photocurable films S-1 to S-6 obtained in Examples 7-12 are shown. Detailed Implementation

[0052] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0053] Unless otherwise specified, all raw materials used in this invention are commercially available, and all raw materials are expressed in parts by weight.

[0054] Unless otherwise specified, all items can be purchased through regular commercial channels.

[0055] Example 1

[0056] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-HDDA, whose specific preparation process is as follows:

[0057] S1. Add sucrose (0.01 mol), diketene (0.08 mol), and 3 wt% 4-dimethylaminopyridine to a 100 mL flask, then add 40 mL of N,N-dimethylformamide. React in an oil bath at 35 °C for 12 h. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution. Separate the liquids, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, which is the beta-dicarbonyl compound Sacac.

[0058] S2. Add 0.01 mol of beta-dicarbonyl compound Sacac, 0.1 mol of 1,6-hexanediol diacrylate, and 10 mol% of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide, and react at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution, separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, namely the bio-based self-sensitive acrylate monomer Sacac-HDDA;

[0059] The NMR and IR results of the beta-dicarbonyl compound Sacac are as follows:

[0060] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 5.61–4.62 ppm (6H, ring hydrogen), 4.43–3.92 ppm (8H, aliphatic O-CH2-CH), 3.68–3.44 ppm (10H, aliphatic C(O)-CH2-C(O)), and 2.20–2.12 ppm (15H, aliphatic C(O)-CH3). Based on this... 1 ¹H NMR analysis revealed that the degree of substitution of the acetoacetate group in the obtained beta-dicarbonyl compound Sacac was approximately 5; the peak positions in the infrared absorption spectrum were 1739 cm⁻¹. -1 and 1709cm -1 (Ester C=O);

[0061] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-HDDA are as follows:

[0062] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.28–5.90 ppm (30H, CH2=CH-), 5.61–4.62 ppm (6H, ring hydrogen), 4.59–3.77 ppm (48H, -O-CH2-CH), 2.34–1.80 ppm (55H, -CH2-CH2-C=O-, -CH3), and 1.58–1.33 ppm (80H, -CH2-CH2-CH2-CH2-). Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹. -1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0063] Example 2

[0064] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-GMA-AA, whose specific preparation process is as follows:

[0065] S1. Same as Example 1;

[0066] S2. Add 0.01 mol of Sacac (containing beta-dicarbonyl compound), 0.1 mol of 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol, and 10 mol% DBU to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide, and react at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution, separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, namely the bio-based self-sensitive acrylate monomer Sacac-GMA-AA;

[0067] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-GMA-AA are as follows:

[0068] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.07 ppm (10H, CH2=CH-), 5.7 ppm (10H, CH2=CH-), 5.61–4.62 ppm (6H, ring hydrogen), 4.59–3.90 ppm (58H, aliphatic O-CH2-CH), 3.57 ppm (5H, -OH), 2.34–1.80 ppm (55H, -CH2-CH2-C=O-, -CH3), and 1.88 ppm (30H, -CH3); Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹.-1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0069] Example 3

[0070] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-NPGDA, whose specific preparation process is as follows:

[0071] S1. Same as Example 1;

[0072] S2. Add 0.01 mol of beta-dicarbonyl compound Sacac, 0.1 mol of neopentyl glycol diacrylate, and 10 mol% DBU to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide, and react at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution, separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, namely the bio-based self-photosensitive acrylate monomer Sacac-NPGDA;

[0073] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-NPGDA are as follows:

[0074] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.28–5.90 ppm (30H, CH2=CH-), 5.61–4.62 ppm (6H, ring hydrogen), 4.59–3.90 ppm (48H, aliphatic O-CH2-CH), 2.34–1.80 ppm (55H, -CH2-CH2-C=O-, -CH3), and 1.88 ppm (60H, -CH3); Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹. -1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0075] Example 4

[0076] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-TPGDA, whose specific preparation process is as follows:

[0077] S1. Same as Example 1;

[0078] S2. Add 0.01 mol of beta-dicarbonyl compound Sacac, 0.1 mol of tripropylene glycol diacrylate, and 10 mol% DBU to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide. React at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution. Separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, namely the bio-based self-photosensitive acrylate monomer Sacac-TPGDA.

[0079] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-TPGDA are as follows:

[0080] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.28–5.90 ppm (30H, CH2=CH-), 5.61–4.62 ppm (16H, ring hydrogen, -CH(CH3)3), 4.59–3.90 ppm (48H, aliphatic O-CH2-CH), 2.34–1.80 ppm (55H, -CH2-CH2-C=O-, -CH3), and 1.2–0.93 ppm (90H, -CH3); Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹. -1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0081] Example 5

[0082] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-TCDDA, whose specific preparation process is as follows:

[0083] S1. Same as Example 1;

[0084] S2. Add 0.01 mol of Sacac (containing beta-dicarbonyl compound), 0.1 mol of tricyclodecanediethanol diacrylate, and 10 mol% DBU to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide, and react at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution, separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, namely the bio-based self-sensitive acrylate monomer Sacac-TCDDA;

[0085] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-TCDDA are as follows:

[0086] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.28–5.90 ppm (30H, CH2=CH-), 5.61–4.62 ppm (6H, ring hydrogen), 4.59–3.90 ppm (48H, aliphatic O-CH2-CH), and 2.63–0.79 ppm (195H, tricyclodecane, -CH2-CH2-C=O-, -CH3); (e.g.) Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹. -1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0087] Example 6

[0088] This embodiment provides a bio-based self-photosensitive acrylate monomer, Sacac-TMPTA, whose specific preparation process is as follows:

[0089] S1. Same as Example 1;

[0090] S2. Add 0.01 mol of beta-dicarbonyl compound Sacac, 0.1 mol of trimethylolpropane triacrylate, and 10 mol% DBU to a 100 mL beaker, then add 40 mL of N,N-dimethylformamide. React at 90 °C for 12 hours. After the reaction is complete, wash with 1 mol / L dilute hydrochloric acid, then wash with ethyl acetate and saturated sodium chloride aqueous solution. Separate the liquid, retain the organic phase, dry with anhydrous magnesium sulfate, filter, and rotary evaporate to obtain a reddish-brown viscous liquid, which is the bio-based self-photosensitive acrylate monomer Sacac-TMPTA.

[0091] The NMR and IR results of the bio-based photosensitive acrylate monomer Sacac-TMPTA are as follows:

[0092] The chemical shifts in the 400 MHz 1H NMR spectrum of DMSO d6 solvent were 6.28–5.90 ppm (60H, CH2=CH-), 5.61–4.62 ppm (6H, ring hydrogen), 4.59–3.90 ppm (68H, aliphatic -O-CH2-CH), 2.36–1.79 ppm (55H, -CH2-CH2-C=O-, -CH3), 1.48 ppm (20H, -CH2-), and 0.86 ppm (30H, -CH3); Figure 8 As shown, the peak positions in the infrared absorption spectrum are 1712 cm⁻¹.-1 (Ester C=O), 1630cm -1 (-CH=CH2) and 810cm -1 (-CH=CH2).

[0093] Example 7

[0094] This embodiment provides a method for preparing a bio-based photocurable film S-1, the specific preparation process of which is as follows:

[0095] By weight, 1 part of the prepared Sacac-HDDA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TPO, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-1, whose morphology is as follows. Figure 1 .

[0096] Example 8

[0097] This embodiment provides a method for preparing a bio-based photocurable film S-2. The specific preparation process is as follows:

[0098] By weight, 1 part of the prepared Sacac-GMA-AA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TP, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-2, with the following morphology. Figure 2 .

[0099] Example 9

[0100] This embodiment provides a method for preparing a bio-based photocurable film S-3, the specific preparation process of which is as follows:

[0101] By weight, 1 part of the prepared Sacac-NPGDA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TPO, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-3, with the following morphology. Figure 3 .

[0102] Example 10

[0103] This embodiment provides a method for preparing a bio-based photocurable film S-4. The specific preparation process is as follows:

[0104] By weight, 1 part of the prepared Sacac-TPGDA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TPO, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-4, with the following morphology. Figure 4 .

[0105] Example 11

[0106] This embodiment provides a method for preparing a bio-based photocurable film S-5. The specific preparation process is as follows:

[0107] By weight, 1 part of the prepared Sacac-TCDDA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TPO, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-5, with the following morphology. Figure 5 .

[0108] Example 12

[0109] This embodiment provides a method for preparing a bio-based photocurable film S-6, the specific preparation process of which is as follows:

[0110] By weight, 1 part of the prepared Sacac-TMPTA, 0.25 parts of the reactive diluent tetrahydrofuran acrylate, 0.03 parts of the free radical photoinitiator TPO, and 0.015 parts of D1173 were mixed and ultrasonically dissolved until homogeneous. The solution was then coated onto a tinplate sheet using a 250 μm coating applicator. The sheet was then heated and leveled in a 60°C oven for 2 hours, followed by exposure to light at an intensity of 38 mW / cm². 2 Exposure to UV light intensity for 60 seconds yielded a bio-based photocurable film S-6, with the following morphology. Figure 6 .

[0111] Performance testing:

[0112] 1. The ultraviolet absorption spectra of the bio-based self-sensitive acrylate monomers obtained in Examples 1-6 were tested, and the results are as follows: Figure 7 As shown. By Figure 7 It can be seen that the maximum absorption wavelength of the bio-based photosensitive acrylate monomers obtained in Examples 1-6 is between 190-250nm. Therefore, by selecting D1173 with a maximum absorption wavelength of 322nm and TPO with a maximum absorption wavelength of 370nm as a mixed photoinitiator system, the purpose of initiating free radical polymerization can be achieved.

[0113] 2. Infrared spectroscopy was performed on the bio-based self-sensitive acrylate monomers obtained in Examples 1-6, and the results are as follows: Figure 8 As shown. Based on 1712cm -1 (Ester C=O), 1630cm -1 (-CH=CH2), 810cm -1 There is a distinct absorption peak of acrylate near (-CH=CH2), indicating that the surface bifunctional acrylate monomer has been successfully incorporated.

[0114] 3. Infrared spectroscopy tests were performed on the bio-based photocurable films S-1 to S-6 obtained in Examples 7-12, and the results are as follows: Figure 9 As shown. 810cm -1 The characteristic absorption peak of the acrylate double bond was significantly weakened, which proves that the double bond in the bio-based photocurable film has basically reacted completely.

[0115] 4. Thermogravimetric properties of the bio-based photocurable films S-1 to S-6 obtained in Examples 7-12 were tested, and the results are as follows: Figure 10 As shown in the figure, except for S-2 which has a 5% thermal weight loss temperature of 197℃, the 5% thermal weight loss temperatures of the other biological and photocurable films are all around 250℃, with S-5 reaching 260℃. This is due to the cyclic structure in the TCDDA monomer. Therefore, introducing a rigid structure into the side chain can improve the overall heat resistance of the material.

[0116] 5. The bio-based photocurable films S-1 to S-6 obtained in Examples 7-12 were tested for pencil hardness and adhesion. The pencil hardness was tested according to GB / T 6739-1996, and the adhesion was tested according to the American Society for Testing and Materials standard ASTM D3359 "Standard Test Method for Determining Adhesion Grades by Adhesive Tape Test". The results are shown in Table 1.

[0117] Table 1: Hardness and adhesion of bio-based photocurable films S-1 to S-6 obtained in Examples 7-12

[0118] sample hardness Adhesion S-1 4H 4B S-2 5H 4B S-3 5H 4B S-4 5H 4B S-5 4H 4B S-6 5H 4B

[0119] As shown in Table 1, the bio-based photocurable films S-1 to S-6 obtained in Examples 7-12 have a large pencil hardness and good adhesion to tinplate sheets.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this application specification, they can still modify or make equivalent substitutions to the specific implementation of the present invention, but these modifications or changes do not depart from the protection scope of the pending claims of the present invention.

Claims

1. A bio-based self-photosensitive acrylate monomer, characterized in that, It has the structure shown in equation (Ⅰ): Formula (I); wherein, represents a residue after removal of a hydroxyl group from sucrose; X, Y independently of each other are a residue after removal of an acryloyloxy group from a multifunctional acrylate monomer; n is a positive integer between 1 and 8; The multifunctional acrylate monomer is selected from at least one of 1,6-hexanediol di(meth)acrylate, tripropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecanediethanol di(meth)acrylate, 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol, and trimethylolpropane tri(meth)acrylate.

2. The bio-based self-photonic acrylate monomer according to claim 1, characterized in that, It is obtained by reacting a beta-dicarbonyl compound with the polyfunctional acrylate monomer, and the structure of the beta-dicarbonyl compound is shown in formula (II): Formula (II).

3. The bio-based self-photosensitive acrylate monomer according to claim 2, characterized in that, The raw materials for preparing the beta-dicarbonyl compound include diketene and sucrose.

4. The method for preparing the bio-based self-photosensitive acrylate monomer according to any one of claims 1 to 3, characterized in that, The process includes the following steps: mixing a beta-dicarbonyl compound with a multifunctional acrylate monomer, a second catalyst, and a second solvent to carry out a second reaction, followed by purification to obtain the bio-based self-sensitive acrylate monomer.

5. The preparation method according to claim 4, characterized in that, The preparation steps of the beta-dicarbonyl compound include: mixing diketene, sucrose, a first catalyst and a first solvent, carrying out a second reaction, purifying, and obtaining the beta-dicarbonyl compound.

6. A bio-based photocurable film, characterized in that, The raw materials include the bio-based self-photosensitive acrylate monomer as described in any one of claims 1 to 3, or the bio-based self-photosensitive acrylate monomer prepared by the preparation method described in any one of claims 4 to 5.

7. The bio-based photocurable film according to claim 6, characterized in that, The raw materials used in the preparation also include free radical photoinitiators and reactive diluents.

8. The method for preparing the bio-based photocurable film according to any one of claims 6 to 7, characterized in that, The process includes the following steps: after mixing all the raw materials evenly, coating the film, and performing a photocuring reaction to obtain the bio-based photocurable film.

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