阅读说明：本技术 一种乳液型生物基水性光固化树脂及其制备方法和应用 (Emulsion type bio-based waterborne light-cured resin and preparation method and application thereof ) 是由 付长清 邓煜东 闫磊 于 2020-12-30 设计创作，主要内容包括：本发明属于光固化树脂材料领域,具体涉及一种乳液型生物基水性光固化树脂及其制备方法和应用,该方法以生物基材料为原料,经过简单的合成反应制备得到生物基改性多元硫醇和改性多元烯烃,通过乳液聚合法制得乳液型生物基水性光固化树脂。本发明制备的水性光固化树脂为结构中含有过量双键或过量巯基的预聚物乳液,烘干后可通过光固化得到具有交联结构的高性能涂膜。利用本发明制备的乳液型生物基水性光固化树脂,不仅能有效解决传统溶剂型光固化树脂气味大,预聚物制备复杂的缺点,还能引入生物基成分,提高产物可再生碳含量,绿色环保。(The invention belongs to the field of light-cured resin materials, and particularly relates to an emulsion type bio-based water-based light-cured resin, a preparation method and application thereof. The water-based light-cured resin prepared by the invention is prepolymer emulsion with excessive double bonds or excessive sulfydryl in the structure, and a high-performance coating film with a cross-linked structure can be obtained through light curing after drying. The emulsion type bio-based waterborne light-cured resin prepared by the invention not only can effectively overcome the defects of strong smell and complex prepolymer preparation of the traditional solvent type light-cured resin, but also can introduce bio-based components, improve the renewable carbon content of the product, and is green and environment-friendly.)

1. The emulsion type bio-based water-based light-cured resin is characterized by being prepared from the following raw materials in parts by mass:

2. an emulsion-type bio-based aqueous photocurable resin according to claim 1, wherein the modified polythiol has the formula:

3. the emulsion type bio-based aqueous photocurable resin according to claim 2, wherein the modified multi-olefin has a structural formula:

4. the emulsion type bio-based aqueous photocurable resin according to claim 3, wherein the emulsifier is an anionic emulsifier and/or a cationic emulsifier.

5. An emulsion type bio-based water-based light-cured resin according to any one of claims 1 to 4, wherein the co-stabilizer is one or more of hexadecane, hexadecanol, lauryl methacrylate and stearyl methacrylate; the photoinitiator is 2-hydroxy-2-methyl-1-phenyl acetone and/or 2-hydroxy-4- (2-hydroxyethoxy) -2-methyl propiophenone.

6. The preparation method of the emulsion type bio-based water-based light-cured resin as claimed in any one of claims 1 to 5, comprising the steps of:

(1) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain prepolymer emulsion containing excessive sulfydryl;

(2) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain a prepolymer emulsion with excessive double bonds;

(3) and mixing the obtained prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds to obtain the light-cured resin.

7. The method for preparing an emulsion type bio-based waterborne photocurable resin according to claim 6, wherein in the step (1) and the step (2), the intensity of the ultraviolet lamp is 900-1100 mJ/cm independently²The wavelength of the ultraviolet lamp is 360-370 nm independently, and the irradiation time of the ultraviolet lamp is 2-3 h independently.

8. The method for preparing an emulsion type bio-based waterborne photocurable resin according to claim 7, wherein in the step (1), the addition amount of the modified polythiol is 6 to 25 parts, and the addition amount of the modified polyene is 4 to 10 parts; in the step (2), the addition amount of the modified polythiol is 4-20 parts, and the addition amount of the modified polyene hydrocarbon is 6-15 parts.

9. The method for preparing an emulsion type bio-based waterborne photocurable resin according to claim 8, wherein in the step (3), the prepolymer emulsion with excess mercapto groups and the prepolymer emulsion with excess double bonds are added in such a manner that the ratio of the amount of mercapto groups to the amount of double bond substances is 1: 1 to 1.2 in proportion.

10. The use of the emulsion-type bio-based waterborne photocurable resin according to any one of claims 1 to 5 in photocurable coatings and photocurable adhesives.

Technical Field

The invention relates to the technical field of light-cured resin materials, in particular to emulsion type bio-based water-based light-cured resin and a preparation method and application thereof.

Background

In recent years, polymer materials which can be continuously developed are more and more emphasized by scientific researchers due to the characteristics of environmental friendliness and excellent performance, and the bio-based materials are expected to replace petrochemical-based raw materials due to the fact that the bio-based materials structurally contain functional group components similar to petroleum monomers. The bio-based material comes from nature, and generally needs to be modified to a certain extent to be better applied to the preparation of polymer materials. By modifying the bio-based material, not only a considerable amount of renewable carbon content can be reserved, but also a new functional group monomer is introduced by utilizing the reaction sites of the bio-based material, and a more functionalized monomer can be prepared.

The ultraviolet polymerization reaction is that the photosensitive substance generates active particles or radicals to initiate reaction monomers in a system under the action of ultraviolet light, so that cross-linking polymerization reaction is carried out. The technology does not need to use organic solvent, has little pollution to the environment, has high curing speed and saves energy. The ultraviolet polymerization reaction can be classified into a radical photopolymerization system, a cationic photopolymerization system, and a radical/cationic hybrid photopolymerization system according to the difference of the initiation system. At present, radical photopolymerization systems are mainly represented by (meth) acrylate photoinitiated self-polymerization reaction systems, but the self-polymerization reaction systems are limited in application because: firstly, the oxygen inhibition effect is obvious; secondly, the volume shrinkage rate is large in the polymerization process, so that the internal stress of the polymer is increased, and the mechanical property of the polymer is reduced; and thirdly, more residual monomers are left after polymerization, the monomer conversion rate is low, and the like.

The sulfydryl-alkene ultraviolet polymerization reaction refers to the gradual free radical polymerization reaction between a monomer containing more than two sulfydryl groups and a monomer containing unsaturated carbon-carbon double bonds, and compared with the (methyl) acrylate ultraviolet self-polymerization reaction, the sulfydryl-alkene polymerization has the advantages of high monomer conversion rate, no oxygen inhibition polymerization interference, low volume shrinkage rate in the polymerization process, wide adaptability to alkene monomer structures, and more development prospect. However, since mercapto compounds are generally expensive and have an unpleasant odor, the research on mercapto-ene photopolymerization is only in the beginning at present.

Regardless of the photopolymerization system, the conventional photocurable resin mainly comprises two major components, namely a high molecular prepolymer and a reactive diluent, wherein the high molecular oligomer generally has high viscosity, and the reactive diluent must be added to adjust the viscosity and the rheological property during coating. These reactive diluents are volatile and contribute to VOCs, but also to varying degrees of toxicity and irritation. This problem is exacerbated in mercapto-ene curing systems, where on the one hand, mercapto-containing prepolymers are difficult to prepare, whereas commercially available small molecule polythiols have a strong odor.

At present, water-based coatings using water as the dispersion medium have become one of the main directions of coating development, and have the advantages of low viscosity and extremely low VOC, which are easy to adjust. UV light-curable coatings and water-based coating technologies are increasingly attracting attention due to their environmental protection advantages. The water-based light-cured coating combines the advantages of the two and is developed more rapidly in more than 20 years. The aqueous light-cured resin can also be divided into water-dispersed resin and emulsion resin, wherein the water-dispersed resin needs to chemically modify the prepolymer to introduce hydrophilic groups, and the emulsion resin is prepared by emulsifying the prepolymer by adding an emulsifier, so that the water-dispersed light-cured resin has no requirement on the chemical structure of the monomer/prepolymer and is beneficial to obtaining diversified structures and properties. The bio-based material is designed into a required structure through simple chemical modification, the prepared bio-based polythiol and polyene monomers are prepared into the prepolymer emulsion in a one-pot emulsion polymerization mode, and the method has good operability, and the key is to prepare the monomer emulsion with small particle size, good storage stability and excellent performance.

Disclosure of Invention

The invention aims to provide an emulsion type bio-based waterborne light-cured resin with small particle size, good stability and excellent performance, and a preparation method and application thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides an emulsion type bio-based waterborne light-cured resin which is prepared from the following raw materials in parts by mass:

as a preferred technical solution of the present invention, the structural formula of the modified polythiol is:

as a preferred technical solution of the present invention, the structural formula of the modified multiolefin is:

as a preferred embodiment of the present invention, the emulsifier is an anionic emulsifier and/or a cationic emulsifier.

As a preferable technical scheme of the invention, the co-stabilizer is one or more of hexadecane, hexadecanol, lauryl methacrylate and octadecyl methacrylate; the photoinitiator is 2-hydroxy-2-methyl-1-phenyl acetone and/or 2-hydroxy-4- (2-hydroxyethoxy) -2-methyl propiophenone.

The invention provides a preparation method of emulsion type bio-based waterborne light-cured resin, which comprises the following steps:

(1) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain prepolymer emulsion containing excessive sulfydryl;

(2) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain a prepolymer emulsion with excessive double bonds;

(3) and mixing the obtained prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds to obtain the light-cured resin.

As a preferable technical scheme of the invention, in the step (1) and the step (2), the intensity of the ultraviolet lamp is 900-1100 mJ/cm independently²The wavelength of the ultraviolet lamp is 360-370 nm independently, and the irradiation time of the ultraviolet lamp is 2-3 h independently.

In a preferable technical scheme of the invention, in the step (1), the addition amount of the modified polythiol is 6-25 parts, and the addition amount of the modified polyene hydrocarbon is 4-10 parts; in the step (2), the addition amount of the modified polythiol is 4-20 parts, and the addition amount of the modified polyene hydrocarbon is 6-15 parts.

In a preferred embodiment of the present invention, in step (3), the ratio of the amount of the mercapto group-containing excess prepolymer emulsion to the amount of the double bond-containing excess prepolymer emulsion is 1: 1 to 1.2 in proportion.

The invention provides application of emulsion type bio-based waterborne light-cured resin in light-cured coatings and light-cured adhesives.

The invention has the beneficial effects that:

the emulsion type bio-based waterborne light-cured resin prepared by the invention is simple to operate, has an equipment foundation for large-scale production and popularization, and can be widely applied to light-cured coatings and adhesives in the future.

Compared with the existing acrylate water-based light-cured resin and solvent-based mercapto-alkene light-cured resin, the invention has the following advantages:

1. the bio-based water-based light-cured resin prepared by the invention has a main body structure of a bio-based material, is high in renewable carbon content, environment-friendly and degradable, and better conforms to the concept of green chemistry and sustainable development compared with the existing acrylate water-based light-cured resin.

2. The bio-based waterborne light-cured resin is a mercapto-alkene polymerization system, compared with the existing acrylate waterborne light-cured resin, the polymerization mechanism is gradual polymerization, and compared with the chain polymerization of acrylates, the bio-based waterborne light-cured resin has the advantages of high monomer conversion rate, no interference of oxygen inhibition, low volume shrinkage rate in the polymerization process and wide adaptability to alkene monomer structures.

3. Compared with the existing light-cured resin, the bio-based water-based light-cured resin has the advantages of low viscosity, low VOC and low odor, and the monomer does not need to be chemically modified by a water-based method with an additional emulsifier, so that diversified structures and properties can be obtained.

Drawings

FIG. 1 is a nuclear magnetic resonance spectrum of isosorbide-based dithiol monomer (IMASH) in example 1 of the present application;

FIG. 2 is a nuclear magnetic resonance spectrum of eugenol-based diolefin (EUCENE) in example 1 of the present application;

FIG. 3 is a nuclear magnetic resonance spectrum of gallic acid based triene (GAENE) according to example 2 of the present application;

FIG. 4 shows the NMR spectra of gallic acid based trithiol monomer (GASH) in example 3 of this application.

Detailed Description

The invention provides an emulsion type bio-based waterborne light-cured resin which is prepared from the following raw materials in parts by mass:

in the present invention, the modified polythiol is added in an amount of 10 to 50 parts, preferably 20 to 40 parts.

In the invention, the preparation method of the modified polythiol comprises the following steps: mixing the bio-based material, the thiol monomer, the catalyst and the solvent, reacting, adding anhydrous sodium carbonate after the reaction is finished, and standing overnight; and filtering, washing, drying and rotary steaming to obtain the modified polythiol. In the invention, the bio-based material comprises one or more of vegetable oil, isosorbide, gallic acid, quinic acid, cardanol, eugenol, tannic acid, limonene and undecylenic acid; the mercaptan monomer comprises one or more of 3-mercaptopropionic acid, beta-mercaptoethanol, mercaptoacetic acid, 4-hydroxythiophenol, cysteine, 2-mercaptobenzyl alcohol, 4-mercaptobenzoic acid, 1, 2-ethanedithiol, 1, 6-hexanedithiol, trimethylolpropane tri (3-mercaptopropionic acid) ester and pentaerythritol tetra (3-mercaptopropionate); the catalyst is one or more of toluenesulfonic acid, sulfuric acid, phosphoric acid and anhydrous potassium carbonate; the solvent is one or more of toluene, xylene, dichloromethane, chloroform, acetone and acetonitrile.

In the present invention, the modified polythiol is preferably:

the reaction formula is as follows:

in the preparation method of the modified polythiol, the addition amount of the bio-based material is 2-30 parts, preferably 15 parts; the addition amount of the mercaptan monomer is 5-55 parts, preferably 25 parts; the addition amount of the catalyst is 0.3-5 parts, preferably 3.5 parts; the adding amount of the solvent is 50-100 parts, preferably 75 parts; the amount of the anhydrous sodium carbonate is 5-10 parts, preferably 7.5 parts.

In the invention, the addition amount of the modified multiolefin is 10-25 parts, and preferably 17 parts.

In the invention, the preparation method of the modified multiolefin comprises the following steps: mixing the bio-based material, triethylamine and a solvent, dropwise adding an olefin monomer under an ice-bath condition, and after complete reaction, removing a product, washing, drying, filtering and carrying out rotary evaporation to obtain the modified multi-element olefin. In the invention, the bio-based raw material comprises one or more of vegetable oil, isosorbide, gallic acid, quinic acid, cardanol, eugenol, tannic acid, limonene and undecylenic acid; the olefin monomer comprises one or more of 10-undecylenechloride, 1, 4-diiodobutane, 1, 4-dibromobutane, 1,2, 4-tribromobutane, crotonic acid and 2-methyl-4-pentenoic acid; the solvent comprises one or more of dichloromethane, trichloromethane, acetone and anhydrous potassium carbonate.

In the present invention, the modified multiolefin is preferably:

the reaction formula is as follows:

in the preparation method of the modified multi-element olefin, the addition amount of the bio-based material is 3-20 parts, preferably 15 parts; the addition amount of triethylamine is 2-35 parts, preferably 20 parts; the addition amount of the solvent is 50-100 parts, preferably 75 parts; the amount of the olefin monomer added is 5 to 70 parts, preferably 55 parts.

In the invention, the addition amount of the emulsifier is 1-5 parts, preferably 2.5 parts; the emulsifier is anionic emulsifier and/or cationic emulsifier, preferably dodecyl sulfuric acid and cetyl trimethyl ammonium bromide.

In the invention, the addition amount of the co-stabilizer is 1-4 parts, preferably 2 parts; the co-stabilizer is one or more of hexadecane, hexadecanol, lauryl methacrylate and stearyl methacrylate, and preferably stearyl methacrylate.

In the invention, the addition amount of the photoinitiator is 0.5-2 parts, preferably 1.2 parts; the photoinitiator is 2-hydroxy-2-methyl-1-phenyl acetone (photoinitiator 1173) and/or 2-hydroxy-4- (2-hydroxyethoxy) -2-methyl propiophenone (photoinitiator 2959), preferably 2-hydroxy-4- (2-hydroxyethoxy) -2-methyl propiophenone (photoinitiator 2959).

The invention provides a preparation method of emulsion type bio-based waterborne light-cured resin, which comprises the following steps:

(1) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain prepolymer emulsion containing excessive sulfydryl;

(2) mixing modified polythiol, modified polyene hydrocarbon and auxiliary stabilizer to obtain oil phase; mixing an emulsifier and water to obtain a water phase; mixing the oil phase, the water phase and the photoinitiator, and reacting under an ultraviolet lamp to obtain a prepolymer emulsion with excessive double bonds;

(3) and mixing the obtained prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds to obtain the light-cured resin.

In the invention, in the step (1) and the step (2), the intensity of the ultraviolet lamp is 900-1100 mJ/cm independently²Preferably 1000mJ/cm²(ii) a The wavelength of the ultraviolet lamp is 360-370 nm independently, preferably 365 nm; the time of the ultraviolet lamp irradiation is independently 2-3 h, preferably 2.5 h.

In the invention, in the step (1), the addition amount of the modified polythiol is 6-25 parts, preferably 15 parts; the addition amount of the modified multi-component olefin is 4-10 parts, preferably 8 parts; in the step (2), the addition amount of the modified polythiol is 4-20 parts, preferably 15 parts; the addition amount of the modified multiolefin is 6-15 parts, preferably 10 parts.

In the present invention, in the step (3), the prepolymer emulsion containing excess mercapto groups and the prepolymer emulsion containing excess double bonds are mixed in such a manner that the ratio of the amounts of the mercapto group-and double bond-containing substances is 1: 1-1.2, preferably 1: 1.

the invention provides application of emulsion type bio-based waterborne light-cured resin in light-cured coatings and light-cured adhesives.

The technical solutions provided by the present invention are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention.

Example 1

Synthesis of isosorbide-based dithiol monomer (IMASH): adding 29.23g of isosorbide and 50.95g of 3-mercaptopropionic acid monomer into a 250ml three-necked flask with a water separator and a condenser tube, weighing 4.1g of p-toluenesulfonic acid as a catalyst, taking 100ml of toluene as a solvent, heating an oil bath kettle to the temperature of 110 ℃ in the reaction kettle, stopping the reaction after 8 hours, adding anhydrous sodium carbonate into the product, standing overnight, filtering, washing with saturated saline solution for 3 times, adding anhydrous magnesium sulfate, drying, filtering, and performing rotary evaporation to obtain isosorbide-based dithiol.

Synthesis of eugenol-based diolefin (EUCENE): adding 4.9g of eugenol, 3.4g of triethylamine and 50ml of dichloromethane into a 250ml three-necked flask, dropwise adding 7.3g of 10-undecylenic chloride under the condition of ice-water bath, reacting at low temperature for 20 hours, adding the mixture into a pear-shaped separating funnel, washing with a saturated sodium bicarbonate aqueous solution for three times, washing with a saturated sodium chloride aqueous solution for three times, adding anhydrous magnesium sulfate, drying, filtering, and performing rotary evaporation to obtain the eugenol-based binary olefin.

Preparation of thiol excess prepolymer emulsion: 1.0g of co-stabilizer octadecyl methacrylate was dissolved in 24.18g of IMASH and 9.6g of EUCENE to obtain an oil phase; 1.32g of the emulsifier sodium lauryl sulfate was dissolved in 43.4g of water to give an aqueous phase. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 1.08g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive sulfydryl in the structure.

Preparation of double bond excess prepolymer emulsion: 0.75g of co-stabilizer octadecyl methacrylate was dissolved in the monomer, 18.02g of IMASH and 8.06g of EUCENE, to give an oil phase; the aqueous phase was obtained by dissolving 0.96g of the emulsifier sodium lauryl sulfate in 36.8g of water. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 0.75g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive double bonds in the structure.

Post-curing of the prepolymer emulsion: respectively mixing the prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds according to the ratio of the sulfydryl to the double bonds of 1: 1, adding 1 percent of water-soluble photoinitiator 2959, stirring uniformly, preparing a film on an ABS plastic plate, baking for 10min at 60 ℃, and placing the film on an ultraviolet lamp (1000 mJ/cm)²365nm) to obtain a cured coating 1, wherein the thickness of the dry film is 10-15 mu m, and the performance is tested after film forming.

Example 2

Synthesis of gallic acid base triene (GAENE): 17.2g of gallic acid, 32.1g of triethylamine and 100ml of dichloromethane are added into a 500ml three-necked flask, 66.8g of 10-undecylenic chloride is dropwise added under the condition of ice-water bath, reaction is carried out for 25 hours at low temperature, the mixture is added into a pear-shaped separating funnel, a saturated sodium bicarbonate aqueous solution is washed for three times, a saturated sodium chloride aqueous solution is washed for three times, anhydrous magnesium sulfate is added for drying, filtration and rotary evaporation are carried out, and the isosorbide-based dyadic olefin is obtained.

Preparation of thiol excess prepolymer emulsion: 0.47g of co-stabilizer octadecyl methacrylate was dissolved in 8.22g of IMASH and 6.7g of GAENE monomer to obtain an oil phase; the aqueous phase was obtained by dissolving 0.58g of the emulsifier sodium lauryl sulfate in 25.34g of water. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 0.77g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive sulfydryl in the structure.

Preparation of double bond excess prepolymer emulsion: 0.55g of co-stabilizer octadecyl methacrylate is dissolved in 6.22g of IMASH and 13.42g of GAENE monomer to obtain an oil phase; the aqueous phase was obtained by dissolving 0.76g of emulsifier sodium lauryl sulfate in 33.67g of water. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 0.1g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive double bonds in the structure.

Post-curing of the prepolymer emulsion: respectively mixing the prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds according to the ratio of the sulfydryl to the double bonds of 1: 1, adding 1% of water-soluble photoinitiator 2959, uniformly stirring, preparing a film on three ABS plastic plates, baking for 10min at 60 ℃, curing under an ultraviolet lamp (1000mJ/cm2, 365nm) to obtain a cured coating 2, wherein the dry film thickness is 10-15 mu m, and testing the performance after film formation.

Example 3

Synthesis of gallic acid base trithiol monomer (GASH): adding 3.8g of gallic acid and 7.6g of 3-mercaptopropionic acid monomer into a 100ml three-necked flask with a water separator and a condenser tube, weighing 0.56g of p-toluenesulfonic acid as a catalyst, taking 100ml of toluene as a solvent, heating an oil bath kettle to the temperature of 110 ℃ in the reaction kettle, stopping the reaction after 12h, adding anhydrous sodium carbonate into the product, standing overnight, filtering, washing with saturated salt solution for 3 times, adding anhydrous magnesium sulfate, drying, filtering, and performing rotary evaporation to obtain the quininic acid based ternary mercaptan monomer.

Preparation of thiol excess prepolymer emulsion: 0.36g of co-stabilizer stearyl methacrylate was dissolved in 9.15g of GASH and 5.01g of EUCENE of the monomer to give an oil phase; the aqueous phase was obtained by dissolving 0.48g of emulsifier sodium lauryl sulfate in 19.34g of water. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 0.36g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive sulfydryl in the structure.

Preparation of double bond excess prepolymer emulsion: 0.75g of co-stabilizer stearyl methacrylate was dissolved in the monomer, 4.56g of GASH and 10.03g of EUCENE, to give an oil phase; the aqueous phase was obtained by dissolving 0.96g of the emulsifier sodium lauryl sulfate in 36.8g of water. Adding the oil phase into the water phase, pre-emulsifying by mechanical stirring, and finely emulsifying by dispersing with a homogenizing ultrasonic instrument at a dispersion rate of 400Watt (80%) for 10min to obtain a monomer emulsion. Adding 0.75g of photoinitiator 2959 into the monomer emulsion, uniformly stirring, and carrying out photoinitiated emulsion polymerization reaction for 2.5h by an ultraviolet lamp to finally obtain the prepolymer emulsion with excessive double bonds in the structure.

Post-curing of the prepolymer emulsion: respectively mixing the prepolymer emulsion with excessive sulfydryl and the prepolymer emulsion with excessive double bonds according to the ratio of the sulfydryl to the double bonds of 1: 1, adding 1 percent of water-soluble photoinitiator 2959, uniformly stirring, preparing a film on three ABS plastic plates, baking at 60 ℃ for 10min, and placing the three ABS plastic plates in an ultraviolet lamp (1000 mJ/cm)²365nm) to obtain a cured coating 3, wherein the thickness of the dry film is 10-15 mu m, and the performance is tested after film forming.

The performance test table of the cured coatings obtained in examples 1 to 3 is as follows:

TABLE 1

The embodiments show that the coating obtained by curing the bio-based waterborne light-cured resin into a film has strong adhesive force, good wear resistance and good corrosion resistance, and can be widely applied to light-cured coatings and light-cured adhesives.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.