A moisture-proof and dust-proof epoxy paint and its preparation method

Abstract

This invention discloses a moisture-proof and dust-proof epoxy paint and its preparation method, belonging to the field of coating technology. The moisture-proof and dust-proof epoxy paint disclosed in this invention, by weight, comprises the following raw material components: 100 parts by weight of high-temperature resistant epoxy resin, 0.8-1.2 parts by weight of curing agent, 8-12 parts by weight of waterproof silicone resin, 4-6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10-15 parts by weight of solvent, and 1-3 parts by weight of antistatic agent. The high-temperature resistant epoxy resin is obtained by epoxidation after grafting 1-bromo-4-(trifluorovinyloxy)benzene, cashew nut shell powder, and hexachlorocyclotriphosphazene. The waterproof silicone resin is obtained by polycondensation of 3-glycidyl etheroxypropyltriethoxysilane and tetraethyl orthosilicate followed by end-capping with 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

Description

Technical Field

[0001] This invention relates to a moisture-proof and dust-proof epoxy paint and its preparation method. Background Technology

[0002] With the continuous advancement of industrial technology and the increasing awareness of environmental protection, the coatings industry is also constantly developing and innovating. Among the many types of coatings, epoxy paints are widely used for corrosion protection of various metal surfaces due to their excellent adhesion, chemical resistance, and mechanical strength. However, in specific application environments, such as outdoor equipment, underground pipelines, ships, and marine engineering, the requirements for coating materials are more stringent. They not only need to have good corrosion resistance but also excellent waterproof and dustproof properties to ensure stability and reliability during long-term use.

[0003] While traditional epoxy paints offer a degree of protection, their waterproof and dustproof capabilities often fall short of practical needs in extreme environments. Especially in areas with high humidity or frequent sandstorms, the coating easily absorbs moisture or accumulates dust, leading to a decline in physical properties and even problems such as blistering and peeling, severely impacting the coating's lifespan and protective effectiveness. Furthermore, with increasingly stringent environmental protection requirements, developing environmentally friendly, high-performance epoxy paints has become a research hotspot in the industry.

[0004] To address the above problems, this invention proposes a moisture-proof and dust-proof epoxy paint and its preparation method. Summary of the Invention

[0005] The purpose of this invention is to provide a moisture-proof and dust-proof epoxy paint and its preparation method to solve the technical problems mentioned in the background section.

[0006] The technical solution to achieve the objective of this invention is:

[0007] A moisture-proof and dust-proof epoxy paint, by weight, comprises the following raw material components: 100 parts by weight of high-temperature resistant epoxy resin, 0.8 to 1.2 parts by weight of curing agent, 8 to 12 parts by weight of waterproof silicone resin, 4 to 6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10 to 15 parts by weight of solvent, and 1 to 3 parts by weight of antistatic agent.

[0008] Furthermore, the high-temperature resistant epoxy resin is obtained by epoxidation after grafting 1-bromo-4-(trifluorovinyloxy)benzene, cashew phenol and hexachlorocyclotriphosphazene.

[0009] Furthermore, the waterproof silicone resin is obtained by polycondensation of 3-glycidyl etheroxypropyltriethoxysilane and tetraethyl orthosilicate followed by end-capping with 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

[0010] The present invention also provides a method for preparing a moisture-proof and dust-proof epoxy paint, comprising the following preparation steps: mixing 100 parts by weight of high-temperature resistant epoxy resin, 0.8-1.2 parts by weight of curing agent, 8-12 parts by weight of waterproof silicone resin, 4-6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10-15 parts by weight of solvent, and 1-3 parts by weight of antistatic agent evenly, heating and stirring at 58-62°C for 28-32 minutes, allowing it to stand for curing and defoaming for 10-15 minutes, filtering the resulting clear varnish through a 200-mesh filter cloth after curing, and then pouring it into a spray gun for spraying.

[0011] Further, the preparation method of the high-temperature resistant epoxy resin is as follows: 38-42 parts by weight of cashew phenolic triphosphazene, 6.6-7 parts by weight of formic acid, 0.3-0.5 parts by weight of p-toluenesulfonic acid, 0.1-0.3 parts by weight of stabilizer urea, and 172-176 parts by weight of toluene are sequentially added to a reaction vessel, stirred and dissolved, and heated to 48-52°C. Then, 22-32 parts by weight of hydrogen peroxide solution are added dropwise over 1.5-2.5 hours. After the addition is completed, the temperature is raised to 58-62°C, and the reaction is continued for 3.5-4.5 hours to obtain the high-temperature resistant epoxy resin.

[0012] Further, the preparation method of the cashew phenol-based cyclotriphosphazene is as follows: 11-13 parts by mass of sodium hydride and 176-180 parts by mass of tetrahydrofuran are stirred and mixed. Then, 28-32 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene and 38-42 parts by mass of cashew phenol are added dropwise at -1 to 1°C. After the addition is completed, the temperature is raised to 58-62°C and the reaction is continued for 25-35 min. Then, 13-15 parts by mass of a tetrahydrofuran solution of hexachlorocyclotriphosphazene is added dropwise. After the addition is completed, the temperature is raised to 68-72°C and the reaction is continued for 23-25 ​​h. After the reaction is completed, the mixture is naturally cooled to room temperature to obtain cashew phenol-based cyclotriphosphazene.

[0013] Further, the preparation method of the waterproof silicone resin is as follows: 3.3-3.5 parts by weight of water, 2.5-3.5 parts by weight of ethanol, 0.9-1.1 parts by weight of glacial acetic acid, 9.7-9.9 parts by weight of 3-glycidyl etheroxypropyltriethoxysilane, and 5.1-5.3 parts by weight of tetraethyl orthosilicate are stirred and mixed evenly, heated to 68-72°C and reacted for 2-3 hours. After cooling to room temperature, the small molecule compounds are removed by rotary evaporation at 65-75°C. Then, 6.9-7.1 parts by weight of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane, 0.1 parts by weight of tris(pentafluorophenyl)boron, and 20 parts by weight of toluene are added. The mixture is stirred and reacted at 58-62°C for 11-13 hours. After removing the solvent toluene under reduced pressure, the mixture is purified by silica gel column chromatography using n-hexane as the eluent to obtain the waterproof silicone resin.

[0014] Further, the preparation method of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane is as follows: 6.34 parts by mass of 50-mesh magnesium powder, 0.001 parts by mass of iodine, 45 parts by mass of dichlorodimethylsilane, and 275 parts by mass of tetrahydrofuran are stirred and mixed. Then, 60 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene are added at room temperature. After the mixture begins to exotherm and darken, it is cooled to 0-5°C in an ice bath. After the addition of 1-bromo-4-(trifluorovinyloxy)benzene is completed, the temperature is slowly raised to room temperature over 4.5-5.5 hours. Then, stirring is continued at room temperature for 14-16 hours. The reaction is quenched with 24-26 parts by mass of water and 130-132 parts by mass of hexane. After filtration through silica gel, the mixture is subjected to vacuum distillation to obtain 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

[0015] Furthermore, the solvent is obtained by mixing xylene and butanone in a mass ratio of 5 to 7:4.

[0016] The present invention also provides a method for using a moisture-proof and dust-proof epoxy paint, wherein the moisture-proof and dust-proof epoxy paint is evenly sprayed onto the item to be painted, and then heated to 60-80°C in an inert gas environment and kept at that temperature for 1.5-2.5 hours, then the temperature is increased to 170-190°C at a rate of 1-3°C / min and kept at that temperature for 1.5-2.5 hours, then the temperature is further increased to 190-210°C and kept at that temperature for 2-4 hours, and then cooled to room temperature.

[0017] By adopting the above technical solution, the present invention has the following beneficial effects:

[0018] The moisture-proof and dust-proof epoxy paint disclosed in this invention comprises, by weight, 100 parts by weight of high-temperature resistant epoxy resin, 0.8-1.2 parts by weight of curing agent, 8-12 parts by weight of waterproof silicone resin, 4-6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10-15 parts by weight of solvent, and 1-3 parts by weight of antistatic agent; the high-temperature resistant epoxy resin is obtained by epoxidation after grafting 1-bromo-4-(trifluorovinyloxy)benzene, cashew nut shell powder, and hexachlorocyclotriphosphazene; the waterproof silicone resin is obtained by polycondensation of 3-glycidyl ether oxypropyltriethoxysilane and tetraethyl orthosilicate followed by end-capping with 4-[trifluorovinyl(oxy)phenyl]dimethylsilane; wherein, the high-temperature resistant epoxy resin is used as the base material, and this resin is composed of 1-bromo-4-(trifluorovinyloxy)benzene, cashew nut shell powder, and hexachlorocyclotriphosphazene. The epoxy paint prepared by phosphazene reaction grafting followed by epoxidation not only improves the resin's temperature resistance and chemical stability but also enhances the coating's mechanical strength. Simultaneously, the addition of waterproof silicone resin, which is polycondensed with 3-glycidyl etheroxypropyltriethoxysilane and tetraethyl orthosilicate and then end-capped with 4-[trifluorovinyl(oxy)phenyl]dimethylsilane, forms a dense hydrophobic layer that effectively blocks moisture penetration and reduces dust adsorption. Furthermore, appropriate amounts of defoamer, leveling agent, and solvent ensure the uniformity and smoothness of the coating during application, while the antistatic agent further reduces the electrostatic effect on the coating surface, preventing dust adhesion. The cured moisture-proof and dust-proof epoxy paint prepared by this invention not only exhibits excellent waterproof and dust-proof properties but also significantly improves heat resistance and mechanical properties, making it suitable for long-term protection in various harsh environments.

[0019] First, cashew phenol, derived from the natural product cashew nut shell oil, endows epoxy resin with excellent mechanical properties and thermal stability, as well as superior chemical resistance, high bonding strength, low shrinkage, and biodegradability. Hexachlorocyclotriphosphazene derivatives not only possess good hydrolysis resistance, but the synergistic effect of phosphorus and nitrogen elements in their structure further enhances the resin's heat resistance and halogen-free flame retardant properties. The introduction of 1-bromo-4-(trifluorovinyloxy)benzene, by increasing the rigidity of the molecular chain and leveraging the hydrophobic and oleophobic properties of fluorine, imparts better hydrophobicity and lower surface energy to the resin, reducing the adsorption of moisture and dust, and enhancing the resin's weather resistance and waterproof performance. Grafting 1-bromo-4-(trifluorovinyloxy)benzene, cashew phenol, and hexachlorocyclotriphosphazene followed by epoxidation forms an epoxy resin with a branched structure centered on a phosphazene ring. This branched structure significantly increases the resin's crosslinking density, enhancing the coating's mechanical strength and chemical resistance.

[0020] Secondly, the waterproof silicone resin is produced by polycondensing 3-glycidyl etheroxypropyltriethoxysilane with tetraethyl orthosilicate, followed by end-capping with 4-[trifluorovinyl(oxy)phenyl]dimethylsilane. The introduction of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane not only effectively prevents burst polymerization and gelation that may occur during the polycondensation process, but also endows the silicone resin with excellent hydrophobicity and dust resistance. This is because the fluorocarbon chain in the end-capping group has extremely low surface energy, which can form a dense hydrophobic barrier that effectively prevents the intrusion of moisture and dust. In addition, the stability and chemical inertness of the end-capping group also enhance the overall weather resistance and aging resistance of the resin, ensuring the reliability and stability of the coating during long-term use.

[0021] Finally, during application, the moisture-proof and dust-proof epoxy paint undergoes multi-stage temperature-increasing curing in an inert gas environment. The trifluoroethylene in the cross-linked high-temperature resistant epoxy resin and waterproof silicone resin undergoes high-temperature cross-linking, forming a tighter three-dimensional network structure, which further improves the cross-linking density of the moisture-proof and dust-proof epoxy paint. This not only enhances the mechanical strength and chemical resistance of the coating, but also significantly improves the waterproof and dustproof performance of the coating. At the same time, the inert gas environment effectively avoids the influence of oxygen and other impurities, ensuring the uniformity and controllability of the curing process, thereby guaranteeing the quality and performance of the final coating. Detailed Implementation

[0022] To better understand the above technical solution, the following will provide a detailed explanation of the technical solution in conjunction with specific implementation methods.

[0023] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0024] The following embodiments are only used to illustrate the technical solutions of the present invention more clearly, and should not be used to limit the scope of protection of the present invention.

[0025] The curing agent used is DMP-30;

[0026] The defoamer was obtained by mixing BYK-141 from Guangzhou Daixun Trading Co., Ltd. with a solvent, wherein BYK-141 accounted for 10 wt%.

[0027] The leveling agent was obtained by mixing BYK-306 from Guangzhou Daixun Trading Co., Ltd. with a solvent, wherein BYK-306 accounted for 10 wt%.

[0028] The antistatic agent used is sodium dodecylbenzenesulfonate.

[0029] Example 1

[0030] A method for using a moisture-proof and dust-proof epoxy paint involves uniformly spraying the paint onto a wooden board, then heating it to 60°C in an inert gas environment and holding it there for 1.5 hours, followed by increasing the temperature at 1°C / min to 170°C and holding it there for 1.5 hours, then continuing to increase the temperature to 190°C and holding it there for 2 hours, and finally cooling it to room temperature.

[0031] A method for preparing a moisture-proof and dust-proof epoxy paint includes the following preparation steps: 100 parts by weight of high-temperature resistant epoxy resin, 0.8 parts by weight of curing agent, 8 parts by weight of waterproof silicone resin, 4 parts by weight of defoamer, 5 parts by weight of leveling agent, 10 parts by weight of solvent, and 1 part by weight of antistatic agent are mixed evenly, heated at 58°C and stirred for 28 minutes, allowed to stand for 10 minutes to defoam, and after aging, the resulting clear varnish is filtered through a 200-mesh filter cloth, then poured into a spray gun and awaited spraying.

[0032] The preparation method of the high-temperature resistant epoxy resin is as follows: 38 parts by weight of cashew phenolic triphosphazene, 6.6 parts by weight of formic acid, 0.3 parts by weight of p-toluenesulfonic acid, 0.1 parts by weight of stabilizer urea, and 172 parts by weight of toluene are added sequentially to a reaction vessel, stirred and dissolved, and heated to 48°C. Then, 22 parts by weight of 30% hydrogen peroxide solution are added dropwise, and the addition is completed in 1.5 hours. After the addition is completed, the temperature is raised to 58°C, and the reaction is continued for 3.5 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. The upper organic phase is taken, washed with distilled water until neutral, and finally dried with anhydrous sodium sulfate. Toluene is removed by vacuum distillation to obtain the high-temperature resistant epoxy resin.

[0033] The preparation method of the cashew phenol-based cyclotriphosphazene is as follows: 11 parts by mass of 60 wt% sodium hydride and 176 parts by mass of tetrahydrofuran are stirred and mixed. Then, 28 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene and 38 parts by mass of cashew phenol are added dropwise at -1℃, and the addition is completed within 2 hours. After the addition is completed, the temperature is raised to 58℃ at 2℃ / min, and the reaction is continued for 25 minutes. Then, 13 parts by mass of a 1M hexachlorocyclotriphosphazene tetrahydrofuran solution is added dropwise, and the addition is completed in 3.5 hours. After the addition is completed, the temperature is raised to 68℃ and the reaction is continued for 23 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. First, the THF solvent is removed by vacuum distillation. Unreacted cashew phenol and incompletely substituted byproducts are removed by washing with acetonitrile. Then, the mixture is dissolved in ethyl acetate and washed three times with 5 wt% NaOH. The organic phase is then washed with distilled water until neutral. Finally, the organic phase is dried with anhydrous sodium sulfate and ethyl acetate is removed by vacuum distillation to obtain cashew phenol-based cyclotriphosphazene.

[0034] The preparation method of the waterproof silicone resin is as follows: 3.3 parts by weight of water, 2.5 parts by weight of ethanol, 0.9 parts by weight of glacial acetic acid, 9.7 parts by weight of 3-glycidyl etheroxypropyltriethoxysilane, and 5.1 parts by weight of tetraethyl orthosilicate are stirred and mixed evenly. The mixture is heated to 68°C and reacted for 2 hours. After cooling to room temperature, the solvent and other small molecule compounds are removed by rotary evaporation at 65°C. Then, 6.9 parts by weight of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane, 0.1 parts by weight of tris(pentafluorophenyl)boron, and 20 parts by weight of toluene are added. The mixture is stirred and reacted at 58°C for 11 hours. After removing the solvent toluene under reduced pressure, the mixture is purified by silica gel column chromatography using n-hexane as the eluent to obtain the waterproof silicone resin.

[0035] The preparation method of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane is as follows: 6.34 parts by mass of 50-mesh magnesium powder, 0.001 parts by mass of iodine, 45 parts by mass of dichlorosilane, and 275 parts by mass of tetrahydrofuran are stirred and mixed. Then, 60 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene are added at room temperature. After the mixture begins to exotherm and darken, it is cooled to 0°C in an ice bath. After the addition of 1-bromo-4-(trifluorovinyloxy)benzene is completed, the temperature is slowly raised to room temperature over 4.5 hours. Then, stirring is continued at room temperature for 14 hours. The reaction is quenched with 24 parts by mass of water and 130 parts by mass of hexane. After filtration through silica gel, the mixture is subjected to vacuum distillation to obtain 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

[0036] The solvent is obtained by mixing xylene and butanone in a mass ratio of 5:4.

[0037] Example 2

[0038] A method for applying a moisture-proof and dust-proof epoxy paint involves uniformly spraying the paint onto a wooden board, then heating it to 70°C in an inert gas environment and holding it there for 2 hours, followed by increasing the temperature at 2°C / min to 180°C and holding it there for 2 hours, then continuing to increase the temperature to 200°C and holding it there for 3 hours, and finally cooling it to room temperature.

[0039] A method for preparing a moisture-proof and dust-proof epoxy paint includes the following preparation steps: 100 parts by weight of high-temperature resistant epoxy resin, 1 part by weight of curing agent, 10 parts by weight of waterproof silicone resin, 5 parts by weight of defoamer, 5 parts by weight of leveling agent, 13 parts by weight of solvent, and 2 parts by weight of antistatic agent are mixed evenly, then heated at 60°C and stirred for 30 minutes, allowed to stand for 13 minutes to defoam, and after aging, the resulting clear varnish is filtered through a 200-mesh filter cloth, then poured into a spray gun and awaited spraying.

[0040] The preparation method of the high-temperature resistant epoxy resin is as follows: 40 parts by weight of cashew phenolic triphosphazene, 6.8 parts by weight of formic acid, 0.4 parts by weight of p-toluenesulfonic acid, 0.2 parts by weight of stabilizer urea, and 174 parts by weight of toluene are added sequentially to a reaction vessel, stirred and dissolved, and heated to 50°C. Then, 27 parts by weight of 30% hydrogen peroxide solution are added dropwise over 2 hours. After the addition is completed, the temperature is raised to 60°C and the reaction continues for 4 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. The upper organic phase is taken and washed with distilled water until neutral. Finally, the organic phase is dried with anhydrous sodium sulfate, and toluene is removed by vacuum distillation to obtain the high-temperature resistant epoxy resin.

[0041] The preparation method of the cashew phenol-based cyclotriphosphazene is as follows: 12 parts by mass of 60 wt% sodium hydride and 178 parts by mass of tetrahydrofuran are stirred and mixed. Then, at 0°C, 30 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene and 40 parts by mass of cashew phenol are added dropwise over 2 hours. After the addition is completed, the temperature is increased to 60°C at 3°C / min, and the reaction is continued for 30 minutes. Then, 14 parts by mass of a 1M hexachlorocyclotriphosphazene tetrahydrofuran solution is added dropwise over 4 hours. After the addition is completed, the temperature is increased to 70°C and the reaction is continued for 24 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. First, the THF solvent is removed by vacuum distillation. Unreacted cashew phenol and incompletely substituted byproducts are removed by washing with acetonitrile. Then, the mixture is dissolved in ethyl acetate and washed three times with 5 wt% NaOH. The organic phase is then washed with distilled water until neutral. Finally, the organic phase is dried with anhydrous sodium sulfate and ethyl acetate is removed by vacuum distillation to obtain cashew phenol-based cyclotriphosphazene.

[0042] The preparation method of the waterproof silicone resin is as follows: 3.4 parts by weight of water, 3 parts by weight of ethanol, 1 part by weight of glacial acetic acid, 9.8 parts by weight of 3-glycidyl etheroxypropyltriethoxysilane, and 5.2 parts by weight of tetraethyl orthosilicate are stirred and mixed evenly. The mixture is heated to 70°C and reacted for 2.5 h. After cooling to room temperature, the solvent and other small molecule compounds are removed by rotary evaporation at 70°C. Then, 7 parts by weight of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane, 0.1 parts by weight of tris(pentafluorophenyl)boron, and 20 parts by weight of toluene are added. The mixture is stirred at 60°C and reacted for 12 h. After removing the solvent toluene under reduced pressure, the mixture is purified by silica gel column chromatography using n-hexane as the eluent to obtain the waterproof silicone resin.

[0043] The preparation method of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane is as follows: 6.34 parts by mass of 50-mesh magnesium powder, 0.001 parts by mass of iodine, 45 parts by mass of dichlorosilane, and 275 parts by mass of tetrahydrofuran are stirred and mixed. Then, 60 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene are added at room temperature. After the mixture begins to exotherm and darken, it is cooled to 3°C in an ice bath. After the addition of 1-bromo-4-(trifluorovinyloxy)benzene is completed, the temperature is slowly raised to room temperature within 5 hours. Then, stirring is continued at room temperature for 15 hours. The reaction is quenched with 25 parts by mass of water and 131 parts by mass of hexane. After filtration through silica gel, the mixture is subjected to vacuum distillation to obtain 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

[0044] The solvent is obtained by mixing xylene and butanone in a mass ratio of 6:4.

[0045] Example 3

[0046] A method for applying a moisture-proof and dust-proof epoxy paint involves uniformly spraying the paint onto a wooden board, then heating it to 80°C in an inert gas environment and holding it there for 2.5 hours, followed by increasing the temperature at 3°C / min to 190°C and holding it there for 2.5 hours, then continuing to increase the temperature to 210°C and holding it there for 4 hours, and finally cooling it to room temperature.

[0047] A method for preparing a moisture-proof and dust-proof epoxy paint includes the following preparation steps: 100 parts by weight of high-temperature resistant epoxy resin, 1.2 parts by weight of curing agent, 12 parts by weight of waterproof silicone resin, 6 parts by weight of defoamer, 5 parts by weight of leveling agent, 15 parts by weight of solvent, and 3 parts by weight of antistatic agent are mixed evenly, then heated at 62°C and stirred for 32 minutes, allowed to stand for 15 minutes to defoam, and after aging, the resulting clear varnish is filtered through a 200-mesh filter cloth, then poured into a spray gun and awaited spraying.

[0048] The preparation method of the high-temperature resistant epoxy resin is as follows: 42 parts by weight of cashew phenolic triphosphazene, 7 parts by weight of formic acid, 0.5 parts by weight of p-toluenesulfonic acid, 0.3 parts by weight of stabilizer urea, and 176 parts by weight of toluene are added sequentially to a reaction vessel, stirred and dissolved, and heated to 52°C. Then, 32 parts by weight of 30% hydrogen peroxide solution are added dropwise over 2.5 hours. After the addition is completed, the temperature is raised to 62°C and the reaction continues for 4.5 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. The upper organic phase is taken and washed with distilled water until neutral. Finally, the organic phase is dried with anhydrous sodium sulfate, and toluene is removed by vacuum distillation to obtain the high-temperature resistant epoxy resin.

[0049] The preparation method of the cashew phenol-based cyclotriphosphazene is as follows: 13 parts by mass of 60 wt% sodium hydride and 180 parts by mass of tetrahydrofuran are stirred and mixed. Then, 32 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene and 42 parts by mass of cashew phenol are added dropwise at 1°C, and the addition is completed within 2 hours. After the addition is completed, the temperature is raised to 62°C at 4°C / min, and the reaction is continued for 35 minutes. Then, 15 parts by mass of a 1M hexachlorocyclotriphosphazene tetrahydrofuran solution is added dropwise, and the addition is completed in 4.5 hours. After the addition is completed, the temperature is raised to 72°C and the reaction is continued for 25 hours. After the reaction is completed, the mixture is naturally cooled to room temperature. First, the THF solvent is removed by vacuum distillation. Unreacted cashew phenol and incompletely substituted byproducts are removed by washing with acetonitrile. Then, the mixture is dissolved in ethyl acetate and washed three times with 5 wt% NaOH. The organic phase is then washed with distilled water until neutral. Finally, the organic phase is dried with anhydrous sodium sulfate and ethyl acetate is removed by vacuum distillation to obtain cashew phenol-based cyclotriphosphazene.

[0050] The waterproof silicone resin is prepared as follows: 3.5 parts by weight of water, 3.5 parts by weight of ethanol, 1.1 parts by weight of glacial acetic acid, 9.9 parts by weight of 3-glycidyl etheroxypropyltriethoxysilane, and 5.3 parts by weight of tetraethyl orthosilicate are stirred and mixed evenly. The mixture is heated to 72°C and reacted for 3 hours. After cooling to room temperature, the solvent and other small molecule compounds are removed by rotary evaporation at 75°C. Then, 7.1 parts by weight of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane, 0.1 parts by weight of tris(pentafluorophenyl)boron, and 20 parts by weight of toluene are added. The mixture is stirred at 62°C and reacted for 13 hours. After removing the solvent toluene under reduced pressure, the mixture is purified by silica gel column chromatography using n-hexane as the eluent to obtain the waterproof silicone resin.

[0051] The preparation method of 4-[trifluorovinyl(oxy)phenyl]dimethylsilane is as follows: 6.34 parts by mass of 50-mesh magnesium powder, 0.001 parts by mass of iodine, 45 parts by mass of dichlorosilane, and 275 parts by mass of tetrahydrofuran are stirred and mixed. Then, 60 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene are added at room temperature. After the mixture begins to exotherm and darken, it is cooled to 5°C in an ice bath. After the addition of 1-bromo-4-(trifluorovinyloxy)benzene is completed, the temperature is slowly raised to room temperature over 5.5 hours. Then, stirring is continued at room temperature for 16 hours. The reaction is quenched with 26 parts by mass of water and 132 parts by mass of hexane. After filtration through silica gel, the mixture is distilled under reduced pressure to obtain 4-[trifluorovinyl(oxy)phenyl]dimethylsilane.

[0052] The solvent is obtained by mixing xylene and butanone in a mass ratio of 7:4.

[0053] Comparative Example 1

[0054] The only difference between Comparative Example 1 and Example 2 is that the high-temperature resistant epoxy resin is obtained by epoxidation after grafting cashew phenol with hexachlorocyclotriphosphazene; the other steps and components are the same as in Example 2.

[0055] Comparative Example 2

[0056] The only difference between Comparative Example 2 and Example 2 is that the high-temperature resistant epoxy resin is obtained by epoxidation after cashew phenol reaction grafting; the other steps and components are the same as in Example 2.

[0057] Comparative Example 3

[0058] The only difference between Comparative Example 3 and Example 2 is the raw material composition of the moisture-proof and dust-proof epoxy paint. The raw material composition of the moisture-proof and dust-proof epoxy paint in Comparative Example 3 includes: high-temperature resistant epoxy resin, curing agent, defoamer, leveling agent, solvent, and antistatic agent; the remaining steps and components are the same as in Example 2.

[0059] Comparative Example 4

[0060] The only difference between Comparative Example 4 and Example 2 is the waterproof silicone resin. The waterproof silicone resin in this comparative example is obtained by polycondensation of 3-glycidyl etheroxypropyltriethoxysilane and tetraethyl orthosilicate followed by hexamethyldisiloxane end-capping; the remaining steps and components are the same as in Example 2.

[0061] Comparative Example 5

[0062] The only difference between Comparative Example 5 and Example 2 is the method of using the moisture-proof and dust-proof epoxy paint. In this comparative example, the method of using the moisture-proof and dust-proof epoxy paint is to spray the moisture-proof and dust-proof epoxy paint evenly onto the wooden board, then heat it to 70°C in an inert gas environment and keep it at that temperature for 2 hours, cool it to room temperature, and dry it at room temperature for 24 hours.

[0063] Example of effect

[0064] Dust prevention: 60g of toner powder was crushed, passed through a 300-mesh sieve, and evenly coated onto the wooden boards used in the examples and comparative examples. The wooden boards were tilted at 15°, and the toner powder on the coating was blown parallel to the painted items for 10 minutes using a wind speed of 3m / s. The amount of residual toner powder on the painted items was then measured.

[0065] Waterproofing: The contact angle of deionized water on the wood surface was measured using a wood contact angle meter with paint spraying technology as described in the examples and comparative examples.

[0066] Thermal stability: The initial decomposition temperature T of the mixture of high-temperature resistant epoxy resin and curing agent was determined using a Perkin Elmer Instruments Pyrist TGA thermogravimetric analyzer. 5％ Measurement parameters: nitrogen flow rate 50 mL / min, temperature range room temperature to 850℃, heating rate 10℃ / min.

[0067] Mechanical properties: Tensile properties of the mixture of high-temperature resistant epoxy resin, curing agent, and waterproof silicone resin after curing according to the test examples and comparative examples of GB / T2569; Flexibility of the moisture-proof and dust-proof epoxy paint according to the test examples and comparative examples of GB / T6742.

[0068] Table 1 below shows the performance data of the moisture-proof and dust-proof epoxy paints prepared in the examples and comparative examples:

[0069] Table 1

[0070]

[0071]

[0072] As shown in Table 1 above, the moisture-proof and dust-proof epoxy paint prepared in the examples has good dustproof properties, thermal stability, water resistance, and mechanical properties.

[0073] Compared to Example 2, Comparative Example 1 performed worse in terms of dust resistance, thermal stability, water resistance, and mechanical properties. This is because the high-temperature resistant epoxy resin in Comparative Example 1 lacked 1-bromo-4-(trifluorovinyloxy)benzene. This component not only reduces surface energy, improves hydrophobicity, and reduces dust adsorption, but also enhances the resin's temperature resistance, chemical stability, and the formation of a tighter cross-linked structure, thereby comprehensively improving the various properties of the coating in Example 2.

[0074] Compared to Example 2, Comparative Example 2 performed worse in terms of dust resistance, thermal stability, water resistance, and mechanical properties because it did not contain hexachlorocyclotriphosphazene, which can significantly improve the hydrophobicity of the coating, reduce surface energy, enhance heat resistance and halogen-free flame retardant properties, and promote the formation of a more stable cross-linked structure.

[0075] Compared to Example 2, Comparative Example 3 performed worse in terms of dust resistance, thermal stability, water resistance, and mechanical properties. This is because Comparative Example 3 lacks waterproof silicone resin, which forms a hydrophobic layer that can effectively reduce dust adsorption, improve the waterproof performance of the coating, and also improve the mechanical strength of the coating.

[0076] Compared to Example 2, Comparative Example 4 performed worse in terms of dust resistance, thermal stability, water resistance, and mechanical properties. The main reason is that the hexamethyldisiloxane-terminated waterproof silicone resin used in Comparative Example 4 is not as good as the 4-[trifluorovinyl(oxy)phenyl]dimethylsilane-terminated waterproof silicone resin in Example 2. The latter has lower surface energy, better hydrophobicity, higher weather resistance and aging resistance, and can form a denser three-dimensional network structure, thereby comprehensively improving the dust resistance, thermal stability, water resistance, and mechanical properties of the coating.

[0077] The main difference between Comparative Example 5 and Example 2 lies in the curing process. Example 2 uses a more complex multi-stage heating curing process, which helps to form a tighter cross-linked network structure and improve the coating's dust resistance, thermal stability, water resistance and mechanical properties.

[0078] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A moisture-proof and dust-proof epoxy paint, characterized in that, By weight, the raw material components include: 100 parts by weight of high-temperature resistant epoxy resin, 0.8 to 1.2 parts by weight of curing agent, 8 to 12 parts by weight of waterproof silicone resin, 4 to 6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10 to 15 parts by weight of solvent, and 1 to 3 parts by weight of antistatic agent. The high-temperature resistant epoxy resin is obtained by epoxidation after grafting 1-bromo-4-(trifluorovinyloxy)benzene, cashew phenol and hexachlorocyclotriphosphazene. The waterproof silicone resin is obtained by polycondensation of 3-glycidyl etheroxypropyltriethoxysilane and tetraethyl orthosilicate followed by end-capping with (4-trifluoroethyleneoxyphenyl)dimethylsilane.

2. A method for preparing a moisture-proof and dust-proof epoxy paint as described in claim 1, characterized in that, The preparation process includes the following steps: 100 parts by weight of high-temperature resistant epoxy resin, 0.8-1.2 parts by weight of curing agent, 8-12 parts by weight of waterproof silicone resin, 4-6 parts by weight of defoamer, 5 parts by weight of leveling agent, 10-15 parts by weight of solvent, and 1-3 parts by weight of antistatic agent are mixed evenly and then heated at 58-62℃ and stirred for 28-32 minutes. After standing and curing for 10-15 minutes to remove foam, the resulting varnish is filtered through a 200-mesh filter cloth and then poured into a spray gun for spraying.

3. The method for preparing the moisture-proof and dust-proof epoxy paint according to claim 2, characterized in that, The preparation method of the high-temperature resistant epoxy resin is as follows: 38-42 parts by weight of cashew phenolic triphosphazene, 6.6-7 parts by weight of formic acid, 0.3-0.5 parts by weight of p-toluenesulfonic acid, 0.1-0.3 parts by weight of stabilizer urea, and 172-176 parts by weight of toluene are added sequentially to a reaction vessel, stirred and dissolved, and heated to 48-52°C. Then, 22-32 parts by weight of hydrogen peroxide solution are added dropwise over 1.5-2.5 hours. After the addition is completed, the temperature is raised to 58-62°C, and the reaction is continued for 3.5-4.5 hours to obtain the high-temperature resistant epoxy resin.

4. The method for preparing the moisture-proof and dust-proof epoxy paint according to claim 3, characterized in that, The preparation method of the cashew phenol-based cyclotriphosphazene is as follows: 11-13 parts by mass of sodium hydride and 176-180 parts by mass of tetrahydrofuran are stirred and mixed. Then, 28-32 parts by mass of 1-bromo-4-(trifluorovinyloxy)benzene and 38-42 parts by mass of cashew phenol are added dropwise at -1 to 1°C. After the addition is completed, the temperature is raised to 58-62°C and the reaction is continued for 25-35 min. Then, 13-15 parts by mass of a tetrahydrofuran solution of hexachlorocyclotriphosphazene is added dropwise. After the addition is completed, the temperature is raised to 68-72°C and the reaction is continued for 23-25 ​​h. After the reaction is completed, the mixture is naturally cooled to room temperature to obtain cashew phenol-based cyclotriphosphazene.

5. The method for preparing the moisture-proof and dust-proof epoxy paint according to claim 3, characterized in that, The preparation method of the waterproof silicone resin is as follows: 3.3-3.5 parts by weight of water, 2.5-3.5 parts by weight of ethanol, 0.9-1.1 parts by weight of glacial acetic acid, 9.7-9.9 parts by weight of 3-glycidyl etheroxypropyltriethoxysilane, and 5.1-5.3 parts by weight of tetraethyl orthosilicate are stirred and mixed evenly. The mixture is heated to 68-72℃ and reacted for 2-3 hours. After cooling to room temperature, the small molecule compounds are removed by rotary evaporation at 65-75℃. Then, 6.9-7.1 parts by weight of (4-trifluoroethyleneoxyphenyl)dimethylsilane, 0.1 parts by weight of tris(pentafluorophenyl)boron, and 20 parts by weight of toluene are added. The mixture is stirred and reacted at 58-62℃ for 11-13 hours. After removing the solvent toluene under reduced pressure, the mixture is purified by silica gel column chromatography using n-hexane as the eluent to obtain the waterproof silicone resin.

6. The method for preparing the moisture-proof and dust-proof epoxy paint according to claim 5, characterized in that, The preparation method of (4-trifluoroethyleneoxyphenyl)dimethylsilane is as follows: 6.34 parts by mass of 50-mesh magnesium powder, 0.001 parts by mass of iodine, 45 parts by mass of dichlorodimethylsilane, and 275 parts by mass of tetrahydrofuran are stirred and mixed. Then, 60 parts by mass of 1-bromo-4-(trifluoroethyleneoxy)benzene are added at room temperature. After the mixture begins to exotherm and darken, it is cooled to 0~5°C in an ice bath. After the addition of 1-bromo-4-(trifluoroethyleneoxy)benzene is completed, the temperature is slowly raised to room temperature over 4.5~5.5 hours. Then, stirring is continued at room temperature for 14~16 hours. The reaction is quenched with 24~26 parts by mass of water and 130~132 parts by mass of hexane. After filtration through silica gel, the mixture is subjected to vacuum distillation to obtain (4-trifluoroethyleneoxyphenyl)dimethylsilane.

7. The method for preparing the moisture-proof and dust-proof epoxy paint according to claim 3, characterized in that, The solvent is obtained by mixing xylene and butanone in a mass ratio of 5 to 7:

4.

8. A method of using the moisture-proof and dust-proof epoxy paint as described in claim 1, characterized in that, Apply the moisture-proof and dust-proof epoxy paint evenly to the item to be painted, then heat it to 60~80℃ in an inert gas environment and keep it at that temperature for 1.5~2.5h. Next, increase the temperature to 170~190℃ at a rate of 1~3℃ / min and keep it at that temperature for 1.5~2.5h. Continue to increase the temperature to 190~210℃ and keep it at that temperature for 2~4h, then cool it to room temperature.

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