Heat dissipating anticorrosive paint and preparation method thereof

Abstract

The application discloses a heat-dissipation type anticorrosive paint and a preparation method thereof, and belongs to the technical field of anticorrosive paint. The heat-dissipation type anticorrosive paint comprises component A and component B. The component A comprises 100 parts by mass of a heat-conducting water-based epoxy resin, 4-6 parts by mass of graphene, 0.3-0.5 parts by mass of an antioxidant, 0.2-0.4 parts by mass of a defoaming agent, 0.2-0.4 parts by mass of a leveling agent, and 10 parts by mass of first deionized water. The component B comprises 10-20 parts by mass of a curing agent, 40-60 parts by mass of a toughening agent, 4-6 parts by mass of functionalized boron nitride microspheres, and 30-50 parts by mass of second deionized water. The heat-conducting water-based epoxy resin is a 1,5-naphthalenediol modified water-based epoxy resin. The curing agent is an aromatic amine curing agent. The toughening agent is obtained by copolymerization of acrylamide, N-(4-aminophenyl) acrylamide, 1,3,5-triacryloyl s-triazine and 3-dimethylaminoallyl phosphate. The functionalized boron nitride microspheres are 4-aminobenzoic acid modified boron nitride microspheres.

Description

TECHNICAL FIELD

[0001] The present application relates to a heat-dissipating anticorrosive coating and a preparation method thereof. BACKGROUND

[0002] With the continuous development of modern industrial technology, especially in the power, chemical industry, shipbuilding and ocean engineering, the equipment working in high temperature or corrosive environment puts forward higher requirements on the performance of materials. As the key factors to ensure the stable operation of equipment, heat dissipation and corrosion protection have attracted much attention in recent years. Although traditional anticorrosive coatings can provide protection to a certain extent, they have obvious shortcomings in terms of thermal conductivity and mechanical properties, and are difficult to meet the application requirements in high heat load environment.

[0003] In recent years, graphene has been widely used in functional composites due to its excellent thermal conductivity, mechanical properties and chemical stability. It has become one of the research hotspots to introduce it into waterborne epoxy resin system to prepare heat-dissipating anticorrosive coating. Graphene modified waterborne epoxy resin coating not only has good environmental performance, but also shows certain heat dissipation and corrosion resistance, which meets the trend of green manufacturing and sustainable development.

[0004] However, there are still many problems in the prior art: (1) the dispersibility of graphene in the resin matrix is poor, and it is easy to agglomerate, which leads to discontinuous heat conduction path and affects the overall heat dissipation efficiency; (2) the corrosion resistance of the coating is easily affected by environmental factors (such as heat and humidity, salt spray, etc.) during long-term use; (3) although the addition of graphene can improve the hardness and modulus of the coating, it often leads to a decrease in impact toughness to adapt to the possible mechanical impact and thermal stress changes under complex working conditions.

[0005] Therefore, the applicant prepared a heat-dissipating anticorrosive coating to solve the above problems. SUMMARY

[0006] The purpose of the present application is to provide a heat-dissipating anticorrosive coating and a preparation method thereof to solve the technical problems mentioned in the background.

[0007] The technical scheme to achieve the purpose of the present application is:

[0008] In a first aspect, the present application provides a heat-dissipating anticorrosive coating, which comprises component A and component B; the component A comprises 100 parts by mass of heat-conducting waterborne epoxy resin, 4-6 parts by mass of graphene, 0.3-0.5 parts by mass of antioxidant, 0.2-0.4 parts by mass of defoaming agent, 0.2-0.4 parts by mass of leveling agent, 10 parts by mass of first deionized water; the component B comprises 10-20 parts by mass of curing agent, 40-60 parts by mass of toughening agent, 4-6 parts by mass of functionalized boron nitride microspheres, and 30-50 parts by mass of second deionized water.

[0009] The heat-dissipating anti-corrosion coating of this invention improves the thermal conductivity of the coating by introducing water-conducting epoxy resin, graphene, and functionalized boron nitride microspheres. Simultaneously, the introduction of graphene and functionalized boron nitride microspheres effectively seals microscopic defects in the water-based epoxy coating, extending the diffusion path of corrosive media within the coating, i.e., the "maze effect," thereby enhancing the corrosion resistance of the heat-dissipating anti-corrosion coating. This invention also introduces a toughening agent to improve the impact resistance of the heat-dissipating anti-corrosion coating.

[0010] Furthermore, the water-conducting epoxy resin is a 1,5-naphthol-modified waterborne epoxy resin.

[0011] This invention uses 1,5-naphthol to modify waterborne epoxy resin. The naphthol hydroxyl groups are bonded to the crosslinkable groups on the surface of the epoxy resin to form a structure in which the naphthol ring is linked to the epoxy resin. This forms a regular, ordered, and locally rigid structure inside the epoxy resin, which increases the "order" of the molecular chain and reduces phonon scattering in the heat conduction process, thereby improving the intrinsic thermal conductivity of the epoxy resin.

[0012] The waterborne epoxy resin is at least one of the following: waterborne epoxy resin F0704 from Shenzhen Yoshida Chemical Co., Ltd., waterborne epoxy resin EP137 from Shenzhen Yoshida Chemical Co., Ltd., and waterborne epoxy resin BS2060 from Shenzhen Yoshida Chemical Co., Ltd.

[0013] Furthermore, the curing agent is an aromatic amine curing agent.

[0014] The antioxidants include antioxidant 1010 and antioxidant GM.

[0015] The leveling agent is WSS-304, a leveling agent from Wuseshi New Materials (Hangzhou) Co., Ltd.

[0016] The defoamer is WSS-20B30 from Wuseshi New Materials (Hangzhou) Co., Ltd.

[0017] Furthermore, the toughening agent is obtained by copolymerizing acrylamide, N-(4-aminophenyl)acrylamide, 1,3,5-triacryloxytriazine, and 3-dimethylaminoallyl phosphoric acid. By introducing 1,3,5-triacryloxytriazine to form a branching center, the acrylamide copolymer with the polymer of the monomers acrylamide, N-(4-aminophenyl)acrylamide, and 3-dimethylaminoallyl phosphoric acid as the branched chain can effectively improve the impact resistance of the heat-dissipating anti-corrosion coating while forming cavities in the toughening agent.

[0018] Furthermore, the functionalized boron nitride microspheres are boron nitride microspheres modified with 4-aminobenzoic acid, and the dispersibility of the boron nitride microspheres is improved by introducing 4-aminobenzoic acid on the surface of the boron nitride microspheres.

[0019] In a second aspect, the present invention provides a method for preparing a heat-dissipating anti-corrosion coating as described in the first aspect, comprising the following preparation steps:

[0020] (1) Weigh and prepare each component according to its corresponding mass fraction;

[0021] (2) Component A: Mix the water-conducting epoxy resin and graphene weighed in step (1), stir at 1400-1600 rpm for 14-16 min at room temperature, then ultrasonically disperse for 55-65 min, then add antioxidant, defoamer, leveling agent, and the first deionized water of component A, and continue stirring and dispersing for 10-20 min to obtain component A; the dispersibility of graphene in component A is improved by the π-π interaction between the naphthalene ring in the water-conducting epoxy resin and graphene;

[0022] (3) Component B: Mix the toughening agent, curing agent, functionalized boron nitride microspheres, and 800-2000 parts by weight of 1M hydrochloric acid solution weighed in step (1). Stir at 1400-1600 rpm for 14-16 min at room temperature, then ultrasonically disperse for 55-65 min. Then slowly add ammonium persulfate solution obtained by dissolving 21-41 parts by weight of ammonium persulfate in 400-500 parts by weight of 1M hydrochloric acid solution at 2-4 s / drop. After the addition is complete, stir at -6 to -4℃ for 55-65 min. After the reaction is completed, filter and wash with ice-cold dilute hydrochloric acid for 2 seconds. Wash the mixture 4 times, then wash it with deionized water until the filtrate is neutral. Then dry it in a vacuum oven at 58-62°C for 23-25 ​​hours. After naturally cooling to room temperature, add a second batch of deionized water and stir at 1400-1600 rpm for 25-35 minutes at room temperature to obtain component B. The curing agent and functionalized boron nitride microspheres are uniformly dispersed in the toughening agent. Some of the functionalized boron nitride microspheres and the curing agent enter the toughening agent cavity. The aniline on the functionalized boron nitride microspheres, the aniline on some of the curing agent, and the aniline on the toughening agent side chains react and polymerize to form polyaniline molecular chains that cross-link with the toughening agent.

[0023] (4) Mix component A obtained in step (2) with component B obtained in step (3), stir at 1400-1600 rpm for 14-16 min at room temperature, then ultrasonically disperse for 55-65 min, and continue stirring for 14-16 min to obtain a heat-dissipating anti-corrosion coating.

[0024] After component A and component B are mixed evenly, the graphene and thermally conductive epoxy resin in component A are uniformly dispersed with the toughening agent, curing agent, and functionalized boron nitride microspheres in component B. Graphene forms π-π interactions with polyaniline in component B, further improving the dispersibility of graphene in the heat-dissipating anti-corrosion coating and forming a thermally conductive pathway between graphene, polyaniline molecular chains, and functionalized boron nitride microspheres, thus further improving the thermal conductivity of the heat-dissipating anti-corrosion coating. The unreacted active groups in the toughening agent and curing agent react and crosslink with the thermally conductive epoxy resin. The phosphate groups in the toughening agent interact with the polyaniline molecular chains. When corrosive media penetrates to the metal interface or the coating is damaged, the phosphorus atoms in the toughening agent and the nitrogen atoms in the polyaniline coordinate with the metal ions generated during corrosion, forming a dense complex at the corrosion site, thereby further improving the anti-corrosion performance of the heat-dissipating anti-corrosion coating.

[0025] Further, the preparation steps of the water-conducting epoxy resin are as follows: water-based epoxy resin and 1,5-naphthol are mixed at a mass ratio of 3 to 5:1, stirred and mixed evenly at 90°C, and then 0.005 to 0.01 times the mass of the water-based epoxy resin catalyst ethyltriphenylphosphine bromide is added, and the temperature is raised to 165 to 175°C at a rate of 1.5 to 2.5°C / min and kept at that temperature for 55 to 65 minutes to obtain the water-conducting epoxy resin.

[0026] Further, the preparation steps of the toughening agent are as follows: Under nitrogen protection, 10 parts by mass of acrylamide, 2-3 parts by mass of N-(4-aminophenyl)acrylamide, and 0.088-0.092 parts by mass of 3-dimethylaminoallylphosphine are dissolved in 50 parts by mass of pure water and stirred until fully dissolved. The pH value is adjusted to neutral with 1M sodium hydroxide solution. After heating in a water bath to 44-46°C, 0.036-0.039 parts by mass of initiator solution are added dropwise. After stirring and reacting for 1-3 hours, 0.008-0.012 parts by mass of 1,3,5-triacryloyltriazine are added, and the reaction is continued for 6-8 hours. After cooling to room temperature, the product is washed and precipitated with anhydrous ethanol. This process is repeated 2-4 times. Then, the product is cut into small pieces with scissors, soaked in anhydrous ethanol until hardened, vacuum dried at 40-46°C for 23-25 ​​hours, and pulverized to obtain the toughening agent.

[0027] Furthermore, the initiator solution is obtained by mixing sodium bisulfite, potassium persulfate, and ultrapure water in a molar ratio of 3:5:1.

[0028] Further, the preparation method of the functionalized boron nitride microspheres is as follows: 0.2-0.4 parts by weight of 4-aminobenzoic acid are mixed with 1000 parts by weight of water, heated to 80-100℃, and stirred until dissolved. Then, 400-600 parts by weight of porous boron nitride microspheres are added, and the mixture is stirred at 200-400 rpm for 15-25 min. Then, the mixture is ultrasonically dispersed for 25-35 min. 0.001-0.003 parts by weight of 4-dimethylaminopyridine are added, and the mixture is stirred for 40-50 s. Then, the mixture is centrifuged at 3000 rpm for 7-9 min, filtered, washed 2-4 times with deionized water, and dried at 58-62℃ for 17-19 h to obtain the functionalized boron nitride microspheres.

[0029] By adopting the above technical solution, the present invention has the following beneficial effects:

[0030] (1) The heat-dissipating anti-corrosion coating of the present invention improves the thermal conductivity of the heat-dissipating anti-corrosion coating by introducing hot-conducting epoxy resin, graphene, and functionalized boron nitride microspheres; at the same time, by introducing graphene and functionalized boron nitride microspheres, the micro-defects in the water-based epoxy coating are effectively sealed, and the diffusion path of the corrosive medium in the coating is extended, i.e., the "maze effect", thereby improving the corrosion resistance of the heat-dissipating anti-corrosion coating; the present invention also introduces a toughening agent to improve the impact resistance of the heat-dissipating anti-corrosion coating.

[0031] (2) The present invention uses 1,5-naphthol to modify waterborne epoxy resin. The naphthol hydroxyl group is bonded to the crosslinkable group on the surface of the epoxy resin to form a structure in which the naphthol ring is connected to the epoxy resin. That is, a regular and orderly, locally rigid structure is formed inside the epoxy resin, which increases the "order" of the molecular chain and reduces phonon scattering in the heat conduction process, thereby improving the intrinsic thermal conductivity of the epoxy resin.

[0032] (3) The toughening agent of the present invention is obtained by copolymerizing acrylamide, N-(4-aminophenyl)acrylamide, 1,3,5-triacryloxytriazine and 3-dimethylaminoallyl phosphoric acid. By introducing 1,3,5-triacryloxytriazine to form a branching center, the acrylamide copolymer with the polymer of the monomers acrylamide, N-(4-aminophenyl)acrylamide and 3-dimethylaminoallyl phosphoric acid as the branched chain forms a cavity in the toughening agent, which at the same time allows the toughening agent to be better soluble with water, and can also effectively improve the impact resistance of the heat dissipation type anti-corrosion coating.

[0033] (4) The functional boron nitride microspheres of the present invention are boron nitride microspheres modified with 4-aminobenzoic acid. The dispersibility of boron nitride microspheres is improved by introducing 4-aminobenzoic acid on the surface of boron nitride microspheres.

[0034] (5) When preparing component A of the heat-dissipating anti-corrosion coating of the present invention, the hot-conducting epoxy resin and graphene are first mixed. At this time, the naphthalene ring in the hot-conducting epoxy resin interacts with the naphthalene ring π-π and the water dispersibility of the water-based epoxy resin is utilized to disperse it well in component A.

[0035] (6) In the heat-dissipating anti-corrosion coating component B of the present invention, hydrochloric acid solution and ammonium persulfate are introduced during the mixing and dispersion process of toughening agent, curing agent, and functionalized boron nitride microspheres. The curing agent and functionalized boron nitride microspheres are uniformly dispersed in the toughening agent through the cavities of the toughening agent. At the same time, aniline on the functionalized boron nitride microspheres, aniline on some of the curing agent, and aniline on the toughening agent side chains react and polymerize to form interpenetrating cross-linked polyaniline molecular chains in the toughening agent. When component B is subsequently mixed with component A, component A is uniformly mixed with component B through the cavities of component B. Component A is then incorporated into graphene and water-conducting epoxy resin to... The polyaniline molecular chains in component B form π-π interactions, further enhancing the dispersibility of graphene in heat-dissipating anti-corrosion coatings. This allows graphene to form thermally conductive pathways with the polyaniline molecular chains, functionalized boron nitride microspheres, and thermally conductive epoxy resin, further improving the thermal conductivity of the heat-dissipating anti-corrosion coating. Furthermore, when corrosive media penetrate to the metal interface or the coating is damaged, the nitrogen atoms in the polyaniline molecular chains and the phosphorus atoms on the toughening agent branches can coordinate with the metal ions generated during corrosion, forming dense complexes at the corrosion site, thereby further enhancing the anti-corrosion performance of the heat-dissipating anti-corrosion coating. Detailed Implementation

[0036] To better understand the above technical solution, the following will provide a detailed explanation of the technical solution in conjunction with specific implementation methods.

[0037] 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.

[0038] The raw materials for the examples and comparative examples are as follows:

[0039] The waterborne epoxy resin is F0704 from Shenzhen Yoshida Chemical Co., Ltd.

[0040] The antioxidant used is GM.

[0041] The leveling agent is WSS-304 from Wuseshi New Materials (Hangzhou) Co., Ltd.

[0042] The defoamer is WSS-20B30 from Wuseshi New Materials (Hangzhou) Co., Ltd.

[0043] The curing agent is p-phenylenediamine sulfate.

[0044] The preparation steps of boron nitride microspheres are described in reference "[1] Xu Lang, Shan Qian, Zheng Zhiyuan, et al. Preparation and application of functionalized boron nitride microspheres [J]. China Powder Technology, 2022, 28(03):23-32.DOI:10.13732 / j.issn.1008-5548.2022.03.004." The specific steps are as follows: 5 parts by mass of boron nitride and 10 parts by mass of ammonium bicarbonate are mixed at 320 r / min with spherical ink After 10 hours, the boron nitride was washed three times with deionized water and dried to obtain pretreated boron nitride. 20 parts by mass of pretreated boron nitride and 1000 parts by mass of deionized water were mixed and homogenized at 6000 rpm for 4 hours using a high-speed homogenizer. The mixture was then allowed to stand for 24 hours. The supernatant was collected, and 0.5 parts by mass of polyvinyl alcohol were added and mixed evenly. The mixture was spray-dried at 180°C and then calcined in a tube furnace at 500°C for 32 hours to obtain porous boron nitride microspheres with a D50 of 6 micrometers.

[0045] The preparation method of 3-dimethylaminoallyl phosphoric acid is described in “Gou Shaohua, Gou Guangjun, Ye Zhongbin, et al. Synthesis and performance study of a terpolymer phosphate [J]. Chemical Research and Application, 2011, 23(08): 997-1001.” The specific steps are as follows: 1.2 mol of dimethylamine and 1.2 mol of phosphorous acid are mixed, and 1M dilute hydrochloric acid is added dropwise at 2s / drop until the pH is 1. After the addition is complete, the temperature is raised from room temperature to 85℃ at 3℃ / min, and 1 mol of acrolein is added dropwise at 2s / dropwise. After the addition is complete, the reaction is continued for 2h to end the reaction, and 3-dimethylaminoallyl phosphoric acid is obtained.

[0046] (Example 1)

[0047] A method for preparing a heat-dissipating anti-corrosion coating includes the following preparation steps:

[0048] (1) Weigh and mix the components according to the following mass parts: 100 parts by mass of thermally conductive epoxy resin, 4 parts by mass of graphene, 0.3 parts by mass of antioxidant, 0.2 parts by mass of defoamer, 0.2 parts by mass of leveling agent, 10 parts by mass of first deionized water; 10 parts by mass of curing agent, 60 parts by mass of toughening agent, 4 parts by mass of functionalized boron nitride microspheres, and 30 parts by mass of second deionized water;

[0049] (2) Component A: Mix the water-conducting epoxy resin and graphene weighed in step (1), stir at 1400 rpm for 14 min at room temperature, then ultrasonically disperse for 55 min, then add antioxidant, defoamer, leveling agent and first deionized water of component A, and continue stirring and dispersing for 10 min to obtain component A;

[0050] (3) Component B: The toughening agent, curing agent, functionalized boron nitride microspheres weighed in step (1) are mixed with 800 parts by weight of 1M hydrochloric acid solution. The mixture is stirred at 1400 rpm for 14 min at room temperature, followed by ultrasonic dispersion for 55 min. Then, ammonium persulfate solution obtained by dissolving 21 parts by weight of ammonium persulfate in 400 parts by weight of 1M hydrochloric acid solution is slowly added dropwise at 2 s / drop. After the addition is completed, the mixture is stirred at -6℃ for 55 min. After the reaction is completed, the mixture is filtered and washed twice with ice-cold dilute hydrochloric acid, and then washed with deionized water until the filtrate is neutral. The mixture is then dried in a vacuum oven at 58℃ for 23 h. After naturally cooling to room temperature, a second deionized water is added, and the mixture is stirred at 1400 rpm for 25 min at room temperature to obtain component B.

[0051] (4) Mix component A obtained in step (2) with component B obtained in step (3), stir at 1400 rpm for 14 min at room temperature, then ultrasonically disperse for 55 min, and continue stirring for 14 min to obtain a heat-dissipating anti-corrosion coating.

[0052] The preparation steps of the water-conducting epoxy resin are as follows: water-based epoxy resin and 1,5-naphthol are mixed at a mass ratio of 3:1 and stirred evenly at 90°C. Then, 0.005 times the mass of the water-based epoxy resin catalyst ethyltriphenylphosphine bromide is added, and the temperature is raised to 165°C at 1.5°C / min and kept at the temperature for 55 min to obtain the water-conducting epoxy resin.

[0053] The toughening agent was prepared as follows: Under nitrogen protection, 10 parts by mass of acrylamide, 2 parts by mass of N-(4-aminophenyl)acrylamide, and 0.092 parts by mass of 3-dimethylaminoallylphosphine were dissolved in 50 parts by mass of pure water and stirred until fully dissolved. The pH was adjusted to neutral with 1M sodium hydroxide solution. After heating in a water bath to 44°C, 0.036 parts by mass of initiator solution were added dropwise. After stirring and reacting for 1 hour, 0.008 parts by mass of 1,3,5-triacryloyltriazine were added and the reaction was continued for 6 hours. After cooling to room temperature, the product was washed and precipitated with anhydrous ethanol. This process was repeated twice. The product was then cut into small pieces with scissors, soaked in anhydrous ethanol until hardened, vacuum dried at 40°C for 23 hours, and pulverized to obtain the toughening agent.

[0054] The initiator solution is obtained by mixing sodium bisulfite, potassium persulfate, and ultrapure water in a molar ratio of 3:5:1.

[0055] The preparation method of the functionalized boron nitride microspheres is as follows: 0.2 parts by mass of 4-aminobenzoic acid are mixed with 1000 parts by mass of water, heated to 80°C, and stirred until dissolved. Then, 400 parts by mass of porous boron nitride microspheres are added, stirred at 200 rpm for 15 min, and then ultrasonically dispersed for 25 min. 0.001 parts by mass of 4-dimethylaminopyridine are added, and stirring is continued for 40 s. Then, the mixture is centrifuged at 3000 rpm for 7 min, filtered, washed twice with deionized water, and dried at 58°C for 17 h to obtain functionalized boron nitride microspheres.

[0056] (Example 2)

[0057] A method for preparing a heat-dissipating anti-corrosion coating includes the following preparation steps:

[0058] (1) Weigh and mix the components according to the following mass parts: 100 parts by mass of thermally conductive epoxy resin, 5 parts by mass of graphene, 0.4 parts by mass of antioxidant, 0.3 parts by mass of defoamer, 0.3 parts by mass of leveling agent, 10 parts by mass of first deionized water; 15 parts by mass of curing agent, 50 parts by mass of toughening agent, 5 parts by mass of functionalized boron nitride microspheres, and 40 parts by mass of second deionized water;

[0059] (2) Component A: Mix the water-conducting epoxy resin and graphene weighed in step (1), stir at 1500 rpm for 15 min at room temperature, then ultrasonically disperse for 60 min, then add antioxidant, defoamer, leveling agent and first deionized water of component A, and continue stirring and dispersing for 15 min to obtain component A;

[0060] (3) Component B: The toughening agent, curing agent, functionalized boron nitride microspheres weighed in step (1) are mixed with 1400 parts by weight of 1M hydrochloric acid solution. The mixture is stirred at 1500 rpm for 15 min at room temperature, followed by ultrasonic dispersion for 60 min. Then, ammonium persulfate solution obtained by dissolving 31 parts by weight of ammonium persulfate in 450 parts by weight of 1M hydrochloric acid solution is slowly added dropwise at 3s / drop. After the addition is completed, the mixture is stirred at -5℃ for 60 min. After the reaction is completed, the mixture is filtered and washed 3 times with dilute hydrochloric acid, and then washed with deionized water until the filtrate is neutral. The mixture is then dried in a vacuum oven at 60℃ for 24 h. After naturally cooling to room temperature, a second deionized water is added, and the mixture is stirred at 1500 rpm for 30 min at room temperature to obtain component B.

[0061] (4) Mix component A obtained in step (2) with component B obtained in step (3), stir at 1500 rpm for 15 min at room temperature, then ultrasonically disperse for 60 min, and continue stirring for 15 min to obtain a heat-dissipating anti-corrosion coating.

[0062] The preparation steps of the water-conducting epoxy resin are as follows: water-based epoxy resin and 1,5-naphthol are mixed at a mass ratio of 4:1 and stirred evenly at 90°C. Then, 0.008 times the mass of the water-based epoxy resin catalyst ethyltriphenylphosphine bromide is added, and the temperature is raised to 170°C at 2°C / min and kept at the temperature for 60 min to obtain the water-conducting epoxy resin.

[0063] The toughening agent was prepared as follows: Under nitrogen protection, 10 parts by mass of acrylamide, 2.5 parts by mass of N-(4-aminophenyl)acrylamide, and 0.09 parts by mass of 3-dimethylaminoallylphosphine were dissolved in 50 parts by mass of pure water and stirred until fully dissolved. The pH was adjusted to neutral with 1M sodium hydroxide solution. After heating in a water bath to 45°C, 0.038 parts by mass of initiator solution were added dropwise. After stirring for 2 hours, 0.01 parts by mass of 1,3,5-triacryloyltriazine was added, and the reaction was continued for 7 hours. After cooling to room temperature, the mixture was washed and precipitated with anhydrous ethanol. This process was repeated 3 times. The mixture was then cut into small pieces with scissors, soaked in anhydrous ethanol until hardened, vacuum dried at 45°C for 24 hours, and pulverized to obtain the toughening agent.

[0064] The initiator solution is obtained by mixing sodium bisulfite, potassium persulfate, and ultrapure water in a molar ratio of 3:5:1.

[0065] The preparation method of the functionalized boron nitride microspheres is as follows: 0.3 parts by mass of 4-aminobenzoic acid and 1000 parts by mass of water are mixed, heated to 90°C, and stirred until dissolved. Then, 500 parts by mass of porous boron nitride microspheres are added, stirred at 300 rpm for 20 min, and then ultrasonically dispersed for 30 min. 0.002 parts by mass of 4-dimethylaminopyridine are added, and stirring is continued for 45 s. Then, the mixture is centrifuged at 3000 rpm for 8 min, filtered, washed three times with deionized water, and dried at 60°C for 18 h to obtain functionalized boron nitride microspheres.

[0066] (Example 3)

[0067] A method for preparing a heat-dissipating anti-corrosion coating includes the following preparation steps:

[0068] (1) Weigh and mix the components according to the following mass parts: 100 parts by mass of thermally conductive epoxy resin, 6 parts by mass of graphene, 0.5 parts by mass of antioxidant, 0.4 parts by mass of defoamer, 0.4 parts by mass of leveling agent, 10 parts by mass of first deionized water; 20 parts by mass of curing agent, 40 parts by mass of toughening agent, 6 parts by mass of functionalized boron nitride microspheres, and 50 parts by mass of second deionized water;

[0069] (2) Component A: Mix the water-conducting epoxy resin and graphene weighed in step (1), stir at 1600 rpm for 16 min at room temperature, then ultrasonically disperse for 65 min, then add antioxidant, defoamer, leveling agent and first deionized water of component A, and continue stirring and dispersing for 20 min to obtain component A;

[0070] (3) Component B: The toughening agent, curing agent, functionalized boron nitride microspheres weighed in step (1) are mixed with 2000 parts by weight of 1M hydrochloric acid solution. The mixture is stirred at 1600 rpm for 16 min at room temperature, followed by ultrasonic dispersion for 65 min. Then, ammonium persulfate solution obtained by dissolving 41 parts by weight of ammonium persulfate in 500 parts by weight of 1M hydrochloric acid solution is slowly added dropwise at 4 s / drop. After the addition is completed, the mixture is stirred at -4℃ for 65 min. After the reaction is completed, the mixture is filtered and washed 4 times with ice-cold dilute hydrochloric acid. Then, it is washed with deionized water until the filtrate is neutral. Then, it is dried in a vacuum oven at 62℃ for 25 h. After naturally cooling to room temperature, a second deionized water is added, and the mixture is stirred at 1600 rpm for 35 min at room temperature to obtain component B.

[0071] (4) Mix component A obtained in step (2) with component B obtained in step (3), stir at 1600 rpm for 16 min at room temperature, then ultrasonically disperse for 65 min, and continue stirring for 16 min to obtain a heat-dissipating anti-corrosion coating.

[0072] The preparation steps of the water-conducting epoxy resin are as follows: water-based epoxy resin and 1,5-naphthol are mixed at a mass ratio of 5:1 and stirred at 90°C until uniform. Then, 0.01 times the mass of the water-based epoxy resin catalyst ethyltriphenylphosphine bromide is added, and the temperature is raised to 175°C at 2.5°C / min and kept at the temperature for 65 min to obtain the water-conducting epoxy resin.

[0073] The toughening agent was prepared as follows: Under nitrogen protection, 10 parts by mass of acrylamide, 3 parts by mass of N-(4-aminophenyl)acrylamide, and 0.088 parts by mass of 3-dimethylaminoallylphosphine were dissolved in 50 parts by mass of pure water and stirred until fully dissolved. The pH was adjusted to neutral with 1M sodium hydroxide solution. After heating in a water bath to 46°C, 0.039 parts by mass of initiator solution were added dropwise. After stirring and reacting for 3 hours, 0.012 parts by mass of 1,3,5-triacryloyltriazine were added, and the reaction was continued for 8 hours. After cooling to room temperature, the product was washed and precipitated with anhydrous ethanol. This process was repeated 4 times. The product was then cut into small pieces with scissors, soaked in anhydrous ethanol until hardened, vacuum dried at 46°C for 25 hours, and pulverized to obtain the toughening agent.

[0074] The initiator solution is obtained by mixing sodium bisulfite, potassium persulfate, and ultrapure water in a molar ratio of 3:5:1.

[0075] The preparation method of the functionalized boron nitride microspheres is as follows: 0.4 parts by mass of 4-aminobenzoic acid and 1000 parts by mass of water are mixed, heated to 100°C, and stirred until dissolved. Then, 600 parts by mass of porous boron nitride microspheres are added, stirred at 400 rpm for 25 min, followed by ultrasonic dispersion for 35 min. Then, 0.003 parts by mass of 4-dimethylaminopyridine are added, and stirring is continued for 50 s. Then, the mixture is centrifuged at 3000 rpm for 9 min, filtered, washed 4 times with deionized water, and dried at 62°C for 19 h to obtain functionalized boron nitride microspheres.

[0076] (Comparative Example 1)

[0077] The difference between Comparative Example 1 and Example 2 is that component A is water-based epoxy resin instead of water-conducting epoxy resin, while the other components and steps are the same as in Example 2.

[0078] (Comparative Example 2)

[0079] The difference between Comparative Example 2 and Example 2 is that component B uses 50 nm boron nitride (h-BN) powder functionalized with 4-aminobenzoic acid instead of 4-aminobenzoic acid functionalized boron nitride microspheres. The other components and steps are the same as in Example 2.

[0080] (Comparative Example 3)

[0081] The difference between Comparative Example 3 and Example 2 is that component B only uses 50 parts by mass of curing agent, 5 parts by mass of functionalized boron nitride microspheres, and 40 parts by mass of second deionized water, while the other components and steps are the same as in Example 2.

[0082] (Comparative Example 4)

[0083] The difference between Comparative Example 4 and Example 2 is that the curing agent used is the water-based epoxy curing agent F0705 from Shenzhen Yoshida Chemical Co., Ltd. instead of the p-phenylenediamine sulfate used in Example 2. The remaining components and steps are the same as in Example 2.

[0084] (Comparative Example 5)

[0085] The difference between Comparative Example 5 and Example 2 is that component B only uses 15 parts by mass of curing agent, 50 parts by mass of toughening agent, 5 parts by mass of boron nitride microspheres, and 40 parts by mass of second deionized water. The remaining components and steps are the same as in Example 2.

[0086] (Comparative Example 6)

[0087] The difference between Comparative Example 6 and Example 2 lies in step (3). Step (3) of Comparative Example 6 is as follows:

[0088] (3) Component B: The toughening agent, curing agent and functionalized boron nitride microspheres weighed in step (1) are mixed and stirred at 1500 rpm for 15 min at room temperature, then ultrasonically dispersed for 60 min, then the second deionized water is added and stirred at 1500 rpm for 30 min at room temperature to obtain component B; the remaining components and steps are the same as in Example 2.

[0089] (Example of the effect)

[0090] Table 1 below shows the test results of various performance parameters of the heat-dissipating anti-corrosion coatings prepared in the examples and comparative examples:

[0091] Table 1

[0092]

[0093]

[0094] As shown in Table 1 above, the heat-dissipating anti-corrosion coatings prepared in Examples 1 to 3 have good thermal conductivity, corrosion resistance, and impact resistance, and the coating adhesion is also good.

[0095] The difference between Comparative Example 1 and Example 2 is that component A uses water-based epoxy resin instead of water-conducting water-based epoxy resin. The resulting heat-dissipating anti-corrosion coating has poor thermal conductivity, impact resistance, and coating adhesion. This may be because the reduced dispersibility of graphene leads to the partial peeling off of the heat-dissipating anti-corrosion coating.

[0096] The difference between Comparative Example 2 and Example 2 is that component B uses 50nm boron nitride (h-BN) powder functionalized with 4-aminobenzoic acid instead of boron nitride microspheres functionalized with 4-aminobenzoic acid. The resulting heat-dissipating anti-corrosion coating has reduced thermal conductivity and increased corrosion resistance. This may be because the layered boron nitride forms a labyrinth effect in the heat-dissipating anti-corrosion coating, increasing impact resistance. The boron nitride microspheres can absorb impact energy and play a role in uniform dynamic load, while the sheet-like boron nitride filler in Comparative Example 2 suffers from deteriorated impact performance due to defects such as microbubbles and interfacial voids.

[0097] The difference between Comparative Example 3 and Example 2 is that no toughening agent was added to component B. The resulting heat-dissipating anti-corrosion coating has poor thermal conductivity and impact resistance, the dispersibility of graphene-functionalized boron nitride microspheres is weakened, and some heat-dissipating anti-corrosion coatings peel off.

[0098] The difference between Comparative Example 4 and Example 2 is that the curing agent used is water-based epoxy curing agent F0705 from Shenzhen Yoshida Chemical Co., Ltd., instead of p-phenylenediamine sulfate from Example 2. The resulting heat-dissipating anti-corrosion coating has poor thermal conductivity.

[0099] The difference between Comparative Example 5 and Example 2 is that component B uses boron nitride microspheres instead of 4-aminobenzoic acid functionalized boron nitride microspheres. The dispersibility of the boron nitride microspheres is affected, resulting in poor thermal conductivity and impact resistance of the heat-dissipating anti-corrosion coating, as well as poor coating adhesion.

[0100] The difference between Comparative Example 6 and Example 2 is that in step (3), hydrochloric acid solution and ammonium persulfate were not introduced during the mixing and dispersion of toughening agent, curing agent and functionalized boron nitride microspheres as in Example 2. As a result, the heat-dissipating anti-corrosion coating prepared has poor thermal conductivity, corrosion resistance and impact resistance.

[0101] 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 heat-dissipating anti-corrosion coating, comprising component A and component B; characterized in that, Component A, by weight, comprises 100 parts by weight of thermally conductive epoxy resin, 4-6 parts by weight of graphene, 0.3-0.5 parts by weight of antioxidant, 0.2-0.4 parts by weight of defoamer, 0.2-0.4 parts by weight of leveling agent, and 10 parts by weight of first deionized water; Component B, by weight, comprises 10-20 parts by weight of curing agent, 40-60 parts by weight of toughening agent, 4-6 parts by weight of functionalized boron nitride microspheres, and 30-50 parts by weight of second deionized water. The water-conducting epoxy resin is a 1,5-naphthol-modified waterborne epoxy resin; the toughening agent is obtained by copolymerization of acrylamide, N-(4-aminophenyl)acrylamide, 1,3,5-triacryloyltriazine, and 3-dimethylaminoallyl phosphate; the functionalized boron nitride microspheres are 4-aminobenzoic acid-modified boron nitride microspheres.

2. The heat-dissipating anti-corrosion coating according to claim 1, characterized in that, The curing agent is an aromatic amine curing agent.

3. A method for preparing a heat-dissipating anti-corrosion coating as described in any one of claims 1 to 2, characterized in that, The preparation steps include the following: (1) Weigh and prepare each component according to its corresponding mass fraction; (2) Component A: Mix the water-conducting epoxy resin and graphene weighed in step (1), stir at 1400~1600 rpm for 14~16 min at room temperature, then ultrasonically disperse for 55~65 min, then add antioxidant, defoamer, leveling agent and first deionized water of component A, and continue stirring and dispersing for 10~20 min to obtain component A; (3) Component B: The toughening agent, curing agent, functionalized boron nitride microspheres weighed in step (1) are mixed with 800~2000 parts by weight of 1M hydrochloric acid solution. The mixture is stirred at 1400~1600 rpm for 14~16 min at room temperature, followed by ultrasonic dispersion for 55~65 min. Then, ammonium persulfate solution obtained by dissolving 21~41 parts by weight of ammonium persulfate in 400~500 parts by weight of 1M hydrochloric acid solution is slowly added dropwise at 2~4 s / drop. After the addition is completed, the mixture is stirred at -6~-4℃ for 55~65 min. After the reaction is completed, the mixture is filtered and washed 2~4 times with dilute hydrochloric acid, and then washed with deionized water until the filtrate is neutral. Then, the mixture is dried in a vacuum oven at 58~62℃ for 23~25 h. After naturally cooling to room temperature, a second deionized water is added, and the mixture is stirred at 1400~1600 rpm for 25~35 min at room temperature to obtain component B. (4) Mix component A obtained in step (2) with component B obtained in step (3), stir at 1400~1600 rpm for 14~16 min at room temperature, then ultrasonically disperse for 55~65 min, and continue stirring for 14~16 min to obtain a heat-dissipating anti-corrosion coating.

4. The method for preparing the heat-dissipating anti-corrosion coating according to claim 3, characterized in that, The preparation steps of the water-conducting epoxy resin are as follows: water-based epoxy resin and 1,5-naphthol are mixed at a mass ratio of 3~5:1 and stirred evenly at 90°C. Then, 0.005~0.01 times the mass of the water-based epoxy resin catalyst ethyltriphenylphosphine bromide is added, and the temperature is raised to 165~175°C at a rate of 1.5~2.5°C / min and kept at that temperature for 55~65min to obtain the water-conducting epoxy resin.

5. The method for preparing the heat-dissipating anti-corrosion coating according to claim 3, characterized in that, The toughening agent is prepared as follows: Under nitrogen protection, 10 parts by weight of acrylamide, 2-3 parts by weight of N-(4-aminophenyl)acrylamide, and 0.088-0.092 parts by weight of 3-dimethylaminoallyl phosphoric acid are dissolved in 50 parts by weight of pure water and stirred until fully dissolved. The pH value is adjusted to neutral with 1M sodium hydroxide solution. After heating in a water bath to 44-46°C, 0.036-0.039 parts by weight of initiator solution are added dropwise. After stirring and reacting for 1-3 hours, 0.008-0.012 parts by weight of 1,3,5-triacryloyltriazine are added, and the reaction is continued for 6-8 hours. After cooling to room temperature, the product is washed and precipitated with anhydrous ethanol. This process is repeated 2-4 times. Then, the product is cut into small pieces with scissors, soaked in anhydrous ethanol until hardened, vacuum dried at 40-46°C for 23-25 ​​hours, and pulverized to obtain the toughening agent.

6. The method for preparing the heat-dissipating anti-corrosion coating according to claim 5, characterized in that, The initiator solution is obtained by mixing sodium bisulfite, potassium persulfate, and ultrapure water in a molar ratio of 3:5:

1.

7. The method for preparing the heat-dissipating anti-corrosion coating according to claim 3, characterized in that, The preparation method of the functionalized boron nitride microspheres is as follows: 0.2-0.4 parts by weight of 4-aminobenzoic acid are mixed with 1000 parts by weight of water, heated to 80-100℃, and stirred until dissolved. Then, 400-600 parts by weight of porous boron nitride microspheres are added, and the mixture is stirred at 200-400 rpm for 15-25 min. Then, the mixture is ultrasonically dispersed for 25-35 min. 0.001-0.003 parts by weight of 4-dimethylaminopyridine are added, and the mixture is stirred for 40-50 s. Then, the mixture is centrifuged at 3000 rpm for 7-9 min, filtered, washed 2-4 times with deionized water, and dried at 58-62℃ for 17-19 h to obtain the functionalized boron nitride microspheres.

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