A marine photovoltaic anticorrosive coating composition and a preparation method thereof

Abstract

The application belongs to the technical field of anticorrosive coating and specifically provides an anticorrosive coating composition for offshore photovoltaics and a preparation method thereof. The anticorrosive coating composition for offshore photovoltaics comprises, from inside to outside, a penetration layer and an anticorrosive coating layer; the penetration layer is covered on the surface of steel and is treated by gas penetration and comprises iron, carbon, nitrogen and oxygen elements; the anticorrosive coating layer is covered on the surface of the penetration layer and is a zinc-aluminum coating layer or a composite paint layer; the composite paint layer comprises a primer, an intermediate paint and a modified acrylic polyurethane topcoat; the modified acrylic polyurethane topcoat comprises component A and component B; the component A comprises a hydroxyl acrylic resin, a composite carbon material, basalt fiber, hydroxyethyl cellulose, a leveling agent, a defoaming agent and ethyl acetate; and the component B comprises an HDI type isocyanate curing agent, a modified polyether amine and a dehydrating agent. The anticorrosive coating composition for offshore photovoltaics prepared by the application has good corrosion resistance, salt spray resistance and aging resistance.

Description

Technical Field

[0001] This application belongs to the field of anti-corrosion coating technology, and in particular relates to an anti-corrosion coating composition for marine photovoltaic applications and its preparation method. Background Technology

[0002] Steel structures are increasingly being used in marine energy development projects, such as offshore oil and gas, offshore wind power, and offshore photovoltaic (PV). Offshore PV can effectively utilize the ocean area, fully leverage solar energy resources, and achieve large-scale power generation, solving the problem of limited space for renewable energy utilization on land. Secondly, the relatively stable marine environment and good heat dissipation can reduce the temperature of photovoltaic modules and improve power generation efficiency. However, seawater contains a large amount of dissolved salts, which are highly corrosive, such as chloride and sodium ions. At the same time, seawater is also rich in oxygen, which can promote electrochemical corrosion. Seawater splashes from sea breezes and the adhesion of microorganisms can also exacerbate corrosion on the surface of steel structures, affecting their function and service life.

[0003] To address the problem of surface corrosion in steel structures, surface treatment technologies are frequently employed. Currently, commonly used surface treatment technologies include electroplating, oxide film methods, and coating methods. Among these, coating methods are the most frequently used anti-corrosion measure for steel structures. For example, patent application CN119039818A discloses an anti-corrosion coating for marine environments and its application method. This anti-corrosion coating comprises a composite coating consisting of a primer, intermediate coat, and topcoat loaded with anti-corrosion agents and bactericidal agents for preventing biofouling. The anti-corrosion agents are derived from graphene; the bactericidal agents are derived from cuprous oxide, corrosion inhibitors, or bactericides. The resulting anti-corrosion coating exhibits reduced permeability, improved corrosion resistance, and provides highly effective protection against biofouling.

[0004] The aforementioned documents describe how adding graphene, cuprous oxide, corrosion inhibitors, or bactericides can achieve corrosion inhibition and passivation of metallic materials, effectively suppressing the adhesion and growth of marine organisms on the coating surface, thereby providing highly efficient corrosion protection. However, the direct addition of graphene does not solve the dispersion problem, which may affect the density of the coating. At the same time, the composite coating is relatively thick, which may lead to a weakening of its adhesion to the substrate. Furthermore, it does not modify for the strong ultraviolet radiation and high weather resistance characteristics of marine environments, and its long-term stability may decrease. Summary of the Invention

[0005] To address the aforementioned issues and further improve the corrosion resistance of steel structures while reducing coating thickness, this application provides an anti-corrosion coating composition for marine photovoltaic applications and its preparation method.

[0006] This application first provides an anti-corrosion coating composition for marine photovoltaic applications, which includes, from the inside out: a penetrating layer and an anti-corrosion coating; The permeation layer covers the surface of the steel and is subjected to gas permeation treatment under a controlled atmosphere, including iron, carbon, nitrogen and oxygen elements; the controlled atmosphere is in the volume ratio of permeation catalyst: air: ammonia = 1:1:(5-10), and the permeation catalyst formula includes methanol, ethanol, water and aniline; The anti-corrosion coating covers the surface of the penetrating layer, and the anti-corrosion coating is a zinc-aluminum coating or a composite paint layer; The composite coating layer includes a primer, an intermediate coat, and a modified acrylic polyurethane topcoat. The modified acrylic polyurethane topcoat comprises component A and component B; Component A comprises the following components by weight: 64-68 parts of hydroxyl acrylic resin, 2-4 parts of composite carbon material, 1-3 parts of basalt fiber, 0.3-0.5 parts of hydroxyethyl cellulose, 1.1-1.4 parts of leveling agent, 0.3-0.5 parts of defoamer, and 24-28 parts of ethyl acetate; Component B comprises the following components by weight: 3-4.5 parts of HDI type isocyanate curing agent, 20-50 parts of modified polyetheramine, and 1-3 parts of dehydrating agent.

[0007] Furthermore, the preparation method of the permeation layer includes the following steps: gas permeation treatment of steel under a controlled atmosphere to obtain the permeation layer; the temperature of the gas permeation treatment is 400℃-800℃, and the time is 30min-12h.

[0008] Furthermore, the primer is one of graphene epoxy zinc-rich primer, alkyd primer, and epoxy ester primer; the intermediate paint is one of graphene epoxy micaceous iron oxide, polyurethane, and epoxy micaceous iron oxide intermediate paint.

[0009] Furthermore, the preparation method of the modified acrylic polyurethane topcoat includes the following steps: X1, adding hydroxyl acrylic resin, ethyl acetate, hydroxyethyl cellulose, composite carbon material, basalt fiber, defoamer, and leveling agent in sequence, and dispersing them at high speed to obtain component A; X2, after dispersing the modified polyether amine and dehydrating agent evenly, adding HDI type isocyanate curing agent, and dispersing them at high speed to obtain component B; X3, mixing component A and component B according to the ratio to obtain the modified acrylic polyurethane topcoat.

[0010] Furthermore, in X3, the ratio of component A to component B is 2-3:1.

[0011] Furthermore, the preparation method of the composite carbon material includes the following steps: Y1, the block copolymer P123 reacts with tetraethoxysilane and then reacts with concentrated nitric acid and hydrogen peroxide aqueous solution under reflux to obtain hydroxylated mesoporous silica; Y2, the hydroxylated mesoporous silica and chitosan are subjected to programmed temperature pyrolysis, HF etching and freeze drying to obtain hollow carbon material; Y3, the hollow carbon material is dispersed in deionized water, nickel nitrate and zinc nitrate solution is added, pyrolyzed and then dispersed in silane coupling agent solution, and refluxed to obtain composite carbon material.

[0012] Furthermore, in Y1, the mass ratio of block copolymer P123 to tetraethoxysilane is 1:1.5-3; in Y3, the molar ratio of nickel nitrate to zinc nitrate is 0.5-2:1.

[0013] Furthermore, the preparation method of the modified polyetheramine includes the following steps: reacting polyetheramine with trifluoroethyl methacrylate at room temperature to obtain the modified polyetheramine.

[0014] Furthermore, this application provides a method for preparing an anti-corrosion coating composition for marine photovoltaic applications, comprising the following steps: S1, gas permeation treatment of steel under a controlled atmosphere to obtain a permeation layer; S2, applying an anti-corrosion coating onto the permeation layer by air spraying and drying and curing.

[0015] Furthermore, in S1, the thickness of the penetration layer is 8μm-60μm; in S2, the dry film thickness of the primer is 70-90μm, the dry film thickness of the intermediate paint is 120-140μm, the dry film thickness of the modified acrylic polyurethane topcoat is 60-80μm, and the dry film thickness of the zinc-aluminum coating is 30-40μm.

[0016] Compared with the prior art, this application has the following beneficial effects: In the anti-corrosion coating composition, the permeation layer is treated with gas permeation to absorb carbon, nitrogen and oxygen elements on the substrate surface to form a dense permeation layer, which significantly improves the hardness and surface strength of the material and can effectively isolate moisture and salt. In the anti-corrosion coating, the silanized composite carbon material is incorporated into the fluorine-modified anti-corrosion coating, which significantly improves the anti-corrosion performance, weather resistance and mechanical strength of the anti-corrosion coating composition.

[0017] Silanization treatment enables the composite carbon material and the fluorine-modified anti-corrosion coating to be chemically bonded, improving the interfacial bonding force and enhancing hydrophobicity. Under the catalytic effect of high specific surface area and doped metal, the composite carbon material induces graphitization to form a dense barrier layer, effectively blocking the penetration of water vapor and chloride ions. During carbonization, zinc nitrate is confined and induced to form nano-zinc oxide within the hollow carbon channels, effectively improving the problem of uneven dispersion when nano-zinc oxide is added alone, and enhancing the resistance of the anti-corrosion coating to mechanical wear and ultraviolet aging. Attached Figure Description

[0018] Figure 1 The water contact angle diagrams are shown for the anti-corrosion coating compositions for marine photovoltaic applications after high and low temperature-ultraviolet artificial accelerated aging in Examples 1-5 and Comparative Examples 1-3.

[0019] Figure 2 The adhesion diagrams show the anti-corrosion coating compositions for marine photovoltaic applications after high and low temperature-ultraviolet artificial accelerated aging in Examples 1-5 and Comparative Examples 1-3.

[0020] Figure 3 This is a permeation layer diagram from Example 2.

[0021] Figure 4 The image shows a photovoltaic support product obtained after coating treatment using Example 2.

[0022] Figure 5 The image shows a photovoltaic bracket product obtained after coating treatment using Example 2. Detailed Implementation

[0023] To make the inventive objectives, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. Obviously, the described embodiments are only a portion of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] When using “including,” “having,” and “contains” as described herein, the intention is to cover non-exclusive inclusion, unless an explicit qualifying term such as “only” is used, in which case another component may be added.

[0026] In this application, "at least one" means one or more, such as one, two, or more. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layered" means at least two layers, such as two layers, three layers, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0027] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0028] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, the method comprising steps (a) and (b) indicates that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0029] The present application will be further illustrated by the following examples, but these examples do not limit the scope of the present application.

[0030] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in this application, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. All reagents or instruments whose manufacturers are not specified are conventional products that can be purchased commercially. In addition to the specific methods, equipment, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description in this application, any prior art methods, equipment, and materials similar to or equivalent to those described, used, or made by the methods, equipment, and materials in the embodiments of this application may be used to implement this application.

[0031] Example 1 The preparation method of the modified acrylic polyurethane topcoat in this embodiment is as follows: X1, mix and disperse 40g of hydroxy acrylic resin, 15g of ethyl acetate and 0.3g of hydroxyethyl cellulose evenly, add 2g of composite carbon material and 1g of basalt fiber, disperse evenly at high speed until there are no lumps, then add the remaining 24g of hydroxy acrylic resin, 0.3g of defoamer and 1.1g of leveling agent in sequence at high speed and disperse, then add the remaining 9g of ethyl acetate and stir to prepare component A. X2, after dispersing 20g of modified polyetheramine and 0.1g of dehydrating agent evenly, add 3g of HDI type isocyanate curing agent and disperse at high speed to obtain component B; X3, Component A and Component B are mixed in a 3:1 ratio and stirred for 2-3 minutes until uniformly mixed to obtain the modified acrylic polyurethane topcoat.

[0032] The preparation method of the composite carbon material in this embodiment is as follows: Y1. Weigh 10g of block copolymer P123 into a 1000mL wide-mouth bottle, then add 325mL of deionized water and 50mL of concentrated hydrochloric acid (37wt%). Stir in a 38℃ water bath for 3h. After the block copolymer P123 is completely dissolved, add 15g of tetraethoxysilane. Maintain the reaction system at 38℃ and stir for 24h. After the reaction is complete, transfer the milky white suspension to a hydrothermal reactor and hydrothermally heat at 110℃ for 24h. After hydrothermal treatment, filter the reaction product and dry at 50℃ to obtain mesoporous silica. Add 4g of mesoporous silica to a 500mL round-bottom flask, then add 60mL of concentrated nitric acid and 20mL of hydrogen peroxide aqueous solution. Reflux at 80℃ for 3h. After the reaction is complete, filter the suspension and wash three times with deionized water and anhydrous ethanol. Finally, dry at 50℃ to obtain hydroxylated mesoporous silica.

[0033] Y2, 7.5 g of chitosan and 5 g of hydroxylated mesoporous silica were dispersed in a mixed solution of 100 mL of ethanol-water solution (volume ratio 1:1) and 500 μL of concentrated hydrochloric acid (37 wt%). After stirring in a sealed container at 70 °C for 3 h, the mixture was transferred to an oven at 50 °C and stirred until dry. Then, it was transferred to a tube furnace and heated to 200 °C under vacuum at a rate of 2 °C / min, and held at this temperature for 600 min. The temperature was then increased to 850 °C at a rate of 5 °C / min and pyrolyzed at this temperature for 240 min. After the furnace temperature cooled to room temperature, the resulting composite was descaled with HF aqueous solution to remove the silica template, and finally, hollow carbon material was obtained by freeze-drying.

[0034] Y3. The hollow carbon material powder synthesized in the previous step was dispersed in deionized water and stirred for 30 min. While stirring, 0.1 mol / L nickel nitrate and 0.2 mol / L zinc nitrate solution (molar ratio 0.5:1) were added, and stirring was continued for 2 h. Then, the resulting mixture was centrifuged and vacuum dried, and heated to 800 °C at a heating rate of 5 °C / min under a nitrogen atmosphere. It was then pyrolyzed at this temperature for 240 min and subsequently dispersed in KH550 solution (prepared by mixing 0.1 mL KH550 with 50 mL anhydrous ethanol and 10 mL deionized water). The mixture was refluxed and stirred at 70-80 °C for 4 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain the composite carbon material.

[0035] The preparation method of the modified polyetheramine in this embodiment is as follows: 10g of polyetheramine D230 was added to a three-necked flask equipped with a stirrer and temperature control. 15g of trifluoroethyl methacrylate (TFMA) was added dropwise at room temperature for 1.5h. The mixture was then washed and purified to obtain the modified polyetheramine.

[0036] The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this embodiment is as follows: S1. Q235 steel is put into a shot blasting machine and shot blasted for 10 minutes. Then, gas permeation treatment is carried out under a controlled atmosphere at a temperature of 400℃ for 10 hours to obtain a permeation layer. The controlled atmosphere is composed of a permeation catalyst: air: ammonia = 1:1:5 by volume. The thickness of the permeation layer is 8μm. The permeation catalyst consists of the following components by mass ratio: 10% methanol, 60% ethanol, 5% aniline, and the balance is water.

[0037] S2. Alkyd primer is applied to the prepared steel plate by air spraying. Areas that cannot be sprayed on the back are brushed with a brush. The dry film thickness of the coating is 70μm. It is then dried for 24 hours. After it is fully dry, the coating surface is manually sanded to remove dust, particles and other contaminants until the surface is clean. Next, polyurethane intermediate paint is sprayed, with a dry film thickness of 120μm. It is dried for 24 hours. After it is fully dry, the coating surface (intermediate paint) is manually sanded to remove dust, particles and other contaminants until the surface is clean. Finally, modified acrylic polyurethane topcoat is sprayed, with two coats, and the dry film thickness is 60μm. After curing for 5 days, the anti-corrosion coating composition for marine photovoltaics is obtained.

[0038] Example 2 The preparation method of the modified acrylic polyurethane topcoat in this embodiment is as follows: X1, mix and disperse 40g of hydroxy acrylic resin, 15g of ethyl acetate and 0.4g of hydroxyethyl cellulose evenly, add 3g of composite carbon material and 2g of basalt fiber, disperse evenly at high speed until there are no lumps, then add the remaining 26g of hydroxy acrylic resin, 0.4g of defoamer and 1.2g of leveling agent in sequence at high speed and disperse, then add the remaining 11g of ethyl acetate and stir to prepare component A; X2, after dispersing 30g of modified polyetheramine and 0.2g of dehydrating agent evenly, add 4g of HDI type isocyanate curing agent and disperse at high speed to obtain component B; X3, Component A and Component B are mixed in a ratio of 2.8:1 and stirred for 2-3 minutes until uniformly mixed to obtain modified acrylic polyurethane topcoat.

[0039] The preparation method of the composite carbon material in this embodiment is as follows: Y1. Weigh 10g of block copolymer P123 into a 1000mL wide-mouth bottle, then add 325mL of deionized water and 50mL of concentrated hydrochloric acid (37wt%). Stir in a 38℃ water bath for 3h. After the block copolymer P123 is completely dissolved, add 20.8g of tetraethoxysilane. Maintain the reaction system at 38℃ and stir for 24h. After the reaction is complete, transfer the milky white suspension to a hydrothermal reactor and hydrothermally heat at 110℃ for 24h. After hydrothermal treatment, filter the reaction product and dry at 50℃ to obtain mesoporous silica. Add 4g of mesoporous silica to a 500mL round-bottom flask, then add 60mL of concentrated nitric acid and 20mL of hydrogen peroxide aqueous solution. Reflux at 80℃ for 3h. After the reaction is complete, filter the suspension and wash three times with deionized water and anhydrous ethanol. Finally, dry at 50℃ to obtain hydroxylated mesoporous silica.

[0040] Y2, 7.5 g of chitosan and 5 g of hydroxylated mesoporous silica were dispersed in a mixed solution of 100 mL of ethanol-water solution (volume ratio 1:1) and 500 μL of concentrated hydrochloric acid (37 wt%). After stirring in a sealed container at 70 °C for 3 h, the mixture was transferred to an oven at 50 °C and stirred until dry. Then, it was transferred to a tube furnace and heated to 200 °C under vacuum at a rate of 2 °C / min, and held at this temperature for 600 min. The temperature was then increased to 850 °C at a rate of 5 °C / min and pyrolyzed at this temperature for 240 min. After the furnace temperature cooled to room temperature, the resulting composite was descaled with HF aqueous solution to remove the silica template, and finally, hollow carbon material was obtained by freeze-drying.

[0041] Y3. The hollow carbon material powder synthesized in the previous step was dispersed in deionized water and stirred for 30 min. While stirring, 0.1 mol / L nickel nitrate and 0.2 mol / L zinc nitrate solution (molar ratio 1:1) were added, and stirring was continued for 2 h. Then, the resulting mixture was centrifuged and vacuum dried, and heated to 800 °C at a heating rate of 5 °C / min under a nitrogen atmosphere. It was then pyrolyzed at this temperature for 240 min and subsequently dispersed in KH550 solution (prepared by mixing 0.1 mL KH550 with 50 mL anhydrous ethanol and 10 mL deionized water). The mixture was refluxed and stirred at 70-80 °C for 4 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain the composite carbon material.

[0042] The preparation method of the modified polyetheramine in this embodiment is as follows: 10g of polyetheramine D230 was added to a three-necked flask equipped with a stirrer and temperature control. 16g of trifluoroethyl methacrylate (TFMA) was added dropwise at room temperature for 1.5h. The mixture was then washed and purified to obtain the modified polyetheramine.

[0043] The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this embodiment is as follows: S1. Q235 steel is put into a shot blasting machine and shot blasted for 10 minutes. Then, gas permeation treatment is carried out under a controlled atmosphere at a temperature of 600℃ for 2 hours to obtain a permeation layer. The controlled atmosphere is composed of a permeation catalyst: air: ammonia = 1:1:7 by volume. The thickness of the permeation layer is 9μm. The permeation catalyst consists of the following components by mass ratio: methanol 40%, ethanol 20%, aniline 25%, and the balance is water.

[0044] S2. Graphene epoxy zinc-rich primer is applied to the prepared steel plate via air spraying. Areas inaccessible to the sprayer on the back are brushed with a brush. The dry film thickness of the coating is 80μm. After drying for 24 hours, the coating surface is manually sanded to remove dust, particles, and other contaminants until clean. Next, graphene epoxy micaceous iron oxide intermediate paint is sprayed, with a dry film thickness of 130μm. After drying for 24 hours, the coating surface (intermediate paint) is manually sanded to remove dust, particles, and other contaminants until clean. Finally, modified acrylic polyurethane topcoat is sprayed in two coats, with a dry film thickness of 70μm. After curing for 5 days, the anti-corrosion coating composition for marine photovoltaic applications is obtained.

[0045] Example 3 The preparation method of the modified acrylic polyurethane topcoat in this embodiment is as follows: X1, mix and disperse 40g of hydroxy acrylic resin, 15g of ethyl acetate and 0.5g of hydroxyethyl cellulose evenly, add 4g of composite carbon material and 3g of basalt fiber, disperse evenly at high speed until there are no lumps, then add the remaining 28g of hydroxy acrylic resin, 0.5g of defoamer and 1.4g of leveling agent in sequence at high speed and disperse, then add the remaining 13g of ethyl acetate and stir to prepare component A; X2, after uniformly dispersing 35g of modified polyetheramine and 0.3g of dehydrating agent, add 4.5g of HDI type isocyanate curing agent and disperse at high speed to obtain component B; X3, Component A and Component B are mixed in a ratio of 2.6:1 and stirred for 2-3 minutes until uniformly mixed to obtain modified acrylic polyurethane topcoat.

[0046] The preparation method of the composite carbon material in this embodiment is as follows: Y1. Weigh 10g of block copolymer P123 into a 1000mL wide-mouth bottle, then add 325mL of deionized water and 50mL of concentrated hydrochloric acid (37wt%) sequentially. Stir in a 38℃ water bath for 3h. After the block copolymer P123 is completely dissolved, add 30g of tetraethoxysilane. Maintain the reaction system at 38℃ and stir for 24h. After the reaction is complete, transfer the milky white suspension to a hydrothermal reactor and hydrothermally heat at 110℃ for 24h. After hydrothermal treatment, filter the reaction product and dry at 50℃ to obtain mesoporous silica. Add 4g of mesoporous silica to a 500mL round-bottom flask, then add 60mL of concentrated nitric acid and 20mL of hydrogen peroxide aqueous solution sequentially, and reflux at 80℃ for 3h. After the reaction is complete, filter the suspension and wash three times sequentially with deionized water and anhydrous ethanol. Finally, dry at 50℃ to obtain hydroxylated mesoporous silica.

[0047] Y2, 7.5 g of chitosan and 5 g of hydroxylated mesoporous silica were dispersed in a mixed solution of 100 mL of ethanol-water solution (volume ratio 1:1) and 500 μL of concentrated hydrochloric acid (37 wt%). After stirring in a sealed container at 70 °C for 3 h, the mixture was transferred to an oven at 50 °C and stirred until dry. Then, it was transferred to a tube furnace and heated to 200 °C under vacuum at a rate of 2 °C / min, and held at this temperature for 600 min. The temperature was then increased to 850 °C at a rate of 5 °C / min and pyrolyzed at this temperature for 240 min. After the furnace temperature cooled to room temperature, the resulting composite was descaled with HF aqueous solution to remove the silica template, and finally, hollow carbon material was obtained by freeze-drying.

[0048] Y3. The hollow carbon material powder synthesized in the previous step was dispersed in deionized water and stirred for 30 min. While stirring, 0.1 mol / L nickel nitrate and 0.2 mol / L zinc nitrate solution (molar ratio 2:1) were added, and stirring was continued for 2 h. Then, the resulting mixture was centrifuged and vacuum dried, and heated to 800 °C at a heating rate of 5 °C / min under a nitrogen atmosphere. It was then pyrolyzed at this temperature for 240 min and subsequently dispersed in KH550 solution (prepared by mixing 0.1 mL KH550 with 50 mL anhydrous ethanol and 10 mL deionized water). The mixture was refluxed and stirred at 70-80 °C for 4 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain the composite carbon material.

[0049] The preparation method of the modified polyetheramine in this embodiment is as follows: 10g of polyetheramine D230 was added to a three-necked flask equipped with a stirrer and temperature control. 15.5g of trifluoroethyl methacrylate (TFMA) was added dropwise at room temperature for 1.5h. The mixture was then washed and purified to obtain the modified polyetheramine.

[0050] The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this embodiment is as follows: S1. Q235 steel is put into a shot blasting machine and shot blasted for 10 minutes. Then, gas permeation treatment is carried out under a controlled atmosphere at a temperature of 650℃ for 30 minutes to obtain a permeated layer. The controlled atmosphere is composed of a permeation catalyst: air: ammonia = 1:1:8 by volume. The thickness of the permeated layer is 15μm. The permeation catalyst consists of the following components by mass ratio: methanol 20%, ethanol 40%, aniline 15%, and the balance is water.

[0051] S2. Epoxy ester primer is applied to the prepared steel plate via air spraying. Areas inaccessible to the sprayer on the back are brushed with a brush. The dry film thickness of the coating is 90μm. It is then dried for 24 hours. After complete drying, the coating surface is manually sanded to remove dust, particles, and other contaminants until clean. Next, epoxy micaceous iron oxide intermediate paint is sprayed, with a dry film thickness of 140μm. It is dried for 24 hours. After complete drying, the coating surface (intermediate paint) is manually sanded to remove dust, particles, and other contaminants until clean. Finally, modified acrylic polyurethane topcoat is sprayed in two coats, with a dry film thickness of 80μm. After curing for 5 days, the anti-corrosion coating composition for marine photovoltaic applications is obtained.

[0052] Example 4 This embodiment provides an anti-corrosion coating composition for marine photovoltaic applications. Specifically, refer to Embodiment 2. The difference between Embodiment 2 and Embodiment 2 is that the thickness of the penetration layer is 30 μm, and the anti-corrosion coating is a zinc-aluminum coating with a thickness of 40 μm.

[0053] Example 5 This embodiment provides an anti-corrosion coating composition for marine photovoltaic applications, specifically referring to Embodiment 2. The difference between Embodiment 2 and Embodiment 2 is that the controllable atmosphere for gas permeation treatment is, by volume ratio, a permeation catalyst: air: ammonia = 1:1:10, the temperature is 600℃, the heat preservation time is 12h, and the thickness of the permeation layer is 60μm.

[0054] Comparative Example 1 The preparation method of the composite carbon material in this comparative example is as follows: Y1. Weigh 10g of block copolymer P123 into a 1000mL wide-mouth bottle, then add 325mL of deionized water and 50mL of concentrated hydrochloric acid (37wt%) sequentially. Stir in a 38℃ water bath for 3h. After the block copolymer P123 is completely dissolved, add 30g of tetraethoxysilane. Maintain the reaction system at 38℃ and stir for 24h. After the reaction is complete, transfer the milky white suspension to a hydrothermal reactor and hydrothermally heat at 110℃ for 24h. After hydrothermal treatment, filter the reaction product and dry at 50℃ to obtain mesoporous silica. Add 4g of mesoporous silica to a 500mL round-bottom flask, then add 60mL of concentrated nitric acid and 20mL of hydrogen peroxide aqueous solution sequentially, and reflux at 80℃ for 3h. After the reaction is complete, filter the suspension and wash three times sequentially with deionized water and anhydrous ethanol. Finally, dry at 50℃ to obtain hydroxylated mesoporous silica.

[0055] Y2, 7.5 g of chitosan and 5 g of hydroxylated mesoporous silica were dispersed in a mixed solution of 100 mL of ethanol-water solution (volume ratio 1:1) and 500 μL of concentrated hydrochloric acid (37 wt%). After stirring in a sealed container at 70 °C for 3 h, the mixture was transferred to an oven at 50 °C and stirred until dry. Then, it was transferred to a tube furnace and heated to 200 °C under vacuum at a rate of 2 °C / min, and held at this temperature for 600 min. The temperature was then increased to 850 °C at a rate of 5 °C / min and pyrolyzed at this temperature for 240 min. After the furnace temperature cooled to room temperature, the resulting composite was descaled with HF aqueous solution to remove the silica template, and finally, hollow carbon material was obtained by freeze-drying.

[0056] Y3. The hollow carbon material powder synthesized in the previous step was dispersed in deionized water and stirred for 30 min. While stirring, 0.2 mol / L zinc nitrate solution was added, and stirring was continued for 2 h. Then, the resulting mixture was centrifuged and vacuum dried, and heated to 800 °C at a rate of 5 °C / min under a nitrogen atmosphere. It was then pyrolyzed at this temperature for 240 min and subsequently dispersed in KH550 solution (prepared by mixing 0.1 mL KH550 with 50 mL anhydrous ethanol and 10 mL deionized water). The mixture was refluxed and stirred at 70-80 °C for 4 h. After the reaction was completed, the mixture was centrifuged, washed, and dried to obtain the composite carbon material.

[0057] The preparation method of the modified acrylic polyurethane topcoat in this comparative example is the same as that in Example 2.

[0058] The preparation method of the modified polyetheramine in this comparative example is the same as that in Example 2.

[0059] The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this comparative example is the same as that in Example 2.

[0060] Comparative Example 2 The preparation method of the modified acrylic polyurethane topcoat in this comparative example is as follows: X1, mix and disperse 40g of hydroxy acrylic resin, 15g of ethyl acetate and 0.4g of hydroxyethyl cellulose evenly, add 3g of composite carbon material, disperse evenly at high speed until there are no lumps, then add the remaining 26g of hydroxy acrylic resin, 0.4g of defoamer and 1.2g of leveling agent in sequence at high speed, and add the remaining 11g of ethyl acetate and stir to prepare component A; X2, after dispersing 30g of polyetheramine and 0.2g of dehydrating agent evenly, add 4g of HDI type isocyanate curing agent and disperse at high speed to obtain component B; X3, Component A and Component B are mixed in a ratio of 2.8:1 and stirred for 2-3 minutes until uniformly mixed to obtain modified acrylic polyurethane topcoat.

[0061] The preparation method of the composite carbon material in this comparative example is as follows: Y1. Weigh 10g of block copolymer P123 into a 1000mL wide-mouth bottle, then add 325mL of deionized water and 50mL of concentrated hydrochloric acid (37wt%) sequentially. Stir in a 38℃ water bath for 3h. After the block copolymer P123 is completely dissolved, add 30g of tetraethoxysilane. Maintain the reaction system at 38℃ and stir for 24h. After the reaction is complete, transfer the milky white suspension to a hydrothermal reactor and hydrothermally heat at 110℃ for 24h. After hydrothermal treatment, filter the reaction product and dry at 50℃ to obtain mesoporous silica. Add 4g of mesoporous silica to a 500mL round-bottom flask, then add 60mL of concentrated nitric acid and 20mL of hydrogen peroxide aqueous solution sequentially, and reflux at 80℃ for 3h. After the reaction is complete, filter the suspension and wash three times sequentially with deionized water and anhydrous ethanol. Finally, dry at 50℃ to obtain hydroxylated mesoporous silica.

[0062] Y2, 7.5 g of chitosan and 5 g of hydroxylated mesoporous silica were dispersed in a mixed solution of 100 mL of ethanol-water solution (volume ratio 1:1) and 500 μL of concentrated hydrochloric acid (37 wt%). After stirring in a sealed container at 70 °C for 3 h, the mixture was transferred to an oven at 50 °C and stirred until dry. Then, it was transferred to a tube furnace and heated to 200 °C under vacuum at a rate of 2 °C / min, and held at this temperature for 600 min. The temperature was then increased to 850 °C at a rate of 5 °C / min and pyrolyzed at this temperature for 240 min. After the furnace temperature cooled to room temperature, the resulting composite was descaled with HF aqueous solution to remove the silica template, and finally, the composite carbon material was obtained by freeze-drying.

[0063] The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this comparative example is the same as that in Example 2.

[0064] Comparative Example 3 The preparation method of the anti-corrosion coating composition for marine photovoltaic applications in this comparative example is as follows: Zinc-aluminum coating was sprayed onto the surface of Q235 steel by air spraying, with a coating thickness of 30μm, and cured for 1 day to obtain an anti-corrosion coating composition for marine photovoltaic applications.

[0065] Performance testing High and low temperature alternating accelerated aging test: According to GB / T 2423.22-2012 "Environmental testing - Part 2: Test methods - Test N: Temperature change", the test was conducted using a high and low temperature alternating damp heat test chamber. Test conditions: minimum temperature -25℃, exposure duration 10 min; maximum temperature 55℃, exposure duration 10 min; temperature change rate 2℃ / min.

[0066] UV aging test: UV aging tests were conducted according to GB / T 14522-2008 and GB / T 1865-2009. UV aging test parameters: UV light irradiation wavelength was 340 nm, and irradiation intensity Q = (60±10) W / m². 2 The temperature was 60℃, the irradiation time was 8 hours, the condensation temperature of distilled water was 40℃, and the time was 4 hours. The ultraviolet aging test selected the temperature, humidity, blackboard temperature, spray time cycle, light exposure time, and total test time according to the standard requirements. The irradiation intensity was checked regularly. Three lamps were replaced after 1000 hours of light exposure. The light exposure and total test time were recorded. One cycle of ultraviolet aging is 10 days.

[0067] The high and low temperature-UV accelerated aging test procedure is as follows: First, the sample is subjected to 3 days of high and low temperature cycle aging, and then placed in a UV aging device for 10 days. This process is one cycle. Water contact angle test: According to GB / T 30693—2014 standard, the LSA60Pro water contact angle meter is used to perform static water contact angle test on the coating. The test is conducted for 3 cycles, namely no cycle aging (0), 1 cycle (1), 2 cycles (2), and 3 cycles (3). Coating adhesion test: The test is conducted according to GB / T 5210-2006. Three areas of each sample are randomly tested for 2 cycles.

[0068] Neutral salt spray corrosion test: Tested according to GB / T 10125—2021 standard. The sample is not marked with lines. The corrosion status of the test plate is checked regularly and the test results are recorded.

[0069] The immersion test used a 3.5% NaCl solution for 4 days. Electrochemical testing of the coating was conducted using a three-electrode system at approximately 25°C. A graphite electrode was used as the auxiliary electrode, a saturated calomel electrode as the reference electrode, and the working electrode had an exposed area of ​​1.12 cm². 2 The coating sample was tested at an open circuit potential with a frequency of 1×(10⁻⁶). 5 -10-2 )Hz, AC signal amplitude 30mV.

[0070] Table 1. Performance test results of the marine photovoltaic anti-corrosion compositions of Examples 1-5 and Comparative Examples 1-3 Analyze Examples 1-5 and Comparative Examples 1-3, in conjunction with Table 1, Figures 1-5 It can be seen that by sequentially coating a penetrating layer and an anti-corrosion coating to form a coating composition, and by fluorinating and modifying the anti-corrosion coating and incorporating a composite carbon material containing dispersed nano zinc oxide particles and a dense barrier layer, the anti-corrosion coating composition for marine photovoltaic applications has good resistance to high and low temperature-ultraviolet aging, salt spray resistance, and high impedance.

[0071] analyze Figures 1-5 As shown in Table 1, the anti-corrosion coating composition for marine photovoltaic applications prepared in Comparative Example 1, compared to Examples 1-5, did not contain nickel nitrate, making it difficult to catalyze the graphitization of carbon materials to form a barrier layer, resulting in decreased stability. Consequently, the adhesion of the anti-corrosion coating composition for marine photovoltaic applications in Comparative Example 1 decreased significantly after high and low temperature-UV aging cycles, and the impedance also decreased significantly after salt water immersion. The anti-corrosion coating composition for marine photovoltaic applications prepared in Comparative Example 2, compared to Examples 1-5, did not undergo fluorination modification of the anti-corrosion coating, and did not contain zinc nitrate and nickel nitrate, making it difficult to form a barrier layer and nano-zinc oxide. At the same time, the hydrophobicity was weakened, resulting in a significant decrease in the water contact angle of the anti-corrosion coating composition for marine photovoltaic applications in Comparative Example 2 after high and low temperature-UV aging cycles, weakening the UV aging resistance and significantly reducing the salt spray resistance time. The anti-corrosion coating composition for marine photovoltaic applications prepared in Comparative Example 3, compared to Examples 1-5, lacked a dense permeable layer, resulting in a decreased ability to isolate moisture and salt, thus shortening the salt spray resistance time of the anti-corrosion coating composition for marine photovoltaic applications in Comparative Example 3.

[0072] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A corrosion-resistant coating composition for marine photovoltaic applications, characterized in that, From the inside out, it includes: a penetrating layer and an anti-corrosion coating; The permeation layer covers the surface of the steel and is subjected to gas permeation treatment under a controlled atmosphere, including iron, carbon, nitrogen and oxygen elements; the controlled atmosphere is in the volume ratio of permeation catalyst: air: ammonia = 1:1:(5-10), and the permeation catalyst formula includes methanol, ethanol, water and aniline; The anti-corrosion coating covers the surface of the penetrating layer, and the anti-corrosion coating is a zinc-aluminum coating or a composite paint layer; The composite coating layer includes a primer, an intermediate coat, and a modified acrylic polyurethane topcoat. The modified acrylic polyurethane topcoat comprises component A and component B; Component A comprises the following components by weight: 64-68 parts of hydroxyl acrylic resin, 2-4 parts of composite carbon material, 1-3 parts of basalt fiber, 0.3-0.5 parts of hydroxyethyl cellulose, 1.1-1.4 parts of leveling agent, 0.3-0.5 parts of defoamer, and 24-28 parts of ethyl acetate; Component B comprises the following components by weight: 3-4.5 parts of HDI type isocyanate curing agent, 20-50 parts of modified polyetheramine, and 1-3 parts of dehydrating agent; The preparation method of the composite carbon material includes the following steps: Y1, the block copolymer P123 reacts with tetraethoxysilane and then reacts with concentrated nitric acid and hydrogen peroxide aqueous solution under reflux to obtain hydroxylated mesoporous silica; Y2, the hydroxylated mesoporous silica and chitosan are subjected to programmed temperature pyrolysis, HF etching and freeze drying to obtain hollow carbon material; Y3, the hollow carbon material is dispersed in deionized water, nickel nitrate and zinc nitrate solution is added, pyrolyzed and then dispersed in silane coupling agent solution, and refluxed to obtain composite carbon material; The method for preparing the modified polyetheramine includes the following steps: reacting polyetheramine with trifluoroethyl methacrylate at room temperature to obtain the modified polyetheramine.

2. The anti-corrosion coating composition for marine photovoltaic applications according to claim 1, characterized in that, The method for preparing the permeation layer includes the following steps: gas permeation treatment of steel under a controlled atmosphere to obtain the permeation layer; the temperature of the gas permeation treatment is 400℃-800℃ and the time is 30min-12h.

3. The anti-corrosion coating composition for marine photovoltaic applications according to claim 1, characterized in that, The primer is one of graphene epoxy zinc-rich primer, alkyd primer, and epoxy ester primer; the intermediate paint is one of graphene epoxy micaceous iron oxide, polyurethane, and epoxy micaceous iron oxide intermediate paint.

4. The anti-corrosion coating composition for marine photovoltaic applications according to claim 1, characterized in that, The preparation method of the modified acrylic polyurethane topcoat includes the following steps: X1, adding hydroxyl acrylic resin, ethyl acetate, hydroxyethyl cellulose, composite carbon material, basalt fiber, defoamer, and leveling agent in sequence, and dispersing them at high speed to obtain component A; X2, after dispersing the modified polyetheramine and dehydrating agent evenly, adding HDI type isocyanate curing agent, and dispersing at high speed to obtain component B; X3, mixing component A and component B according to the ratio to obtain the modified acrylic polyurethane topcoat.

5. The anti-corrosion coating composition for marine photovoltaic applications according to claim 4, characterized in that, In X3, the ratio of component A to component B is 2-3:

1.

6. The anti-corrosion coating composition for marine photovoltaic applications according to claim 1, characterized in that, In Y1, the mass ratio of block copolymer P123 to tetraethoxysilane is 1:1.5-3; in Y3, the molar ratio of nickel nitrate to zinc nitrate is 0.5-2:

1.

7. A method for preparing an anti-corrosion coating composition for marine photovoltaic applications as described in any one of claims 1-6, characterized in that, The process includes the following steps: S1, gas permeation treatment of steel under a controlled atmosphere to obtain a permeation layer; S2, application of an anti-corrosion coating onto the permeation layer by air spraying, followed by drying and curing.

8. The method for preparing an anti-corrosion coating composition for marine photovoltaic applications according to claim 7, characterized in that, In S1, the thickness of the penetration layer is 8μm-60μm; in S2, the dry film thickness of the primer is 70-90μm, the dry film thickness of the intermediate paint is 120-140μm, the dry film thickness of the modified acrylic polyurethane topcoat is 60-80μm, and the dry film thickness of the zinc-aluminum coating is 30-40μm.

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