Marine anticorrosive and antifouling coating

Abstract

The application belongs to the field of functional coatings, and particularly relates to a marine corrosion and fouling resistant coating and a preparation method thereof. The marine corrosion and fouling resistant coating is prepared from a two-component coating, and comprises the following raw materials in parts by weight: component A: 20-40 parts of acrylic resin, 5-15 parts of epoxy resin, 3-6 parts of modified graphene filler, 5-10 parts of active metal filler, 8-12 parts of zwitterionic polymer, 5-10 parts of talcum powder, 0.1-0.3 parts of defoaming agent, 0.5-1.0 parts of leveling agent, and 10-20 parts of deionized water; component B: 15-25 parts of waterborne isocyanate curing agent. The marine corrosion and fouling resistant coating is obtained through paint preparation, coating and curing. The marine corrosion and fouling resistant coating can effectively improve the corrosion resistance and the deficiency in biological antifouling performance through formula design and cooperation of the self-prepared modified graphene filler and zwitterionic polymer.

Description

Technical Field

[0001] This invention belongs to the field of functional coatings, specifically relating to a marine anti-corrosion and antifouling coating. Background Technology

[0002] The marine environment is an extremely harsh corrosive environment. Seawater and the marine atmosphere have high salinity, and the corrosive environment is affected by factors such as sunlight, sea breeze, and marine life. Currently, my country is in the initial stage of research on the corrosion mechanism of marine coatings and in the development and application of marine coatings, lagging far behind developed countries. The market prospects for long-lasting marine anti-corrosion coatings are vast. Therefore, it is necessary to vigorously develop marine anti-corrosion coatings with excellent corrosion resistance.

[0003] Zinc and aluminum, among other metals, provide excellent corrosion protection to the metal substrate in coatings, acting as sacrificial anodes and are commonly used anti-corrosion fillers. However, they suffer from short service life. Graphene, as a novel anti-corrosion filler, has attracted widespread attention. Research shows that adding graphene and its derivatives to coatings can significantly improve the coating's impermeability through the stacking of graphene sheets, effectively hindering the penetration of O2, water, and corrosive media, exhibiting a "maze effect," thereby effectively enhancing the coating's corrosion resistance. However, due to the π-π interactions between graphene sheets, its dispersion in coatings is poor, easily leading to problems such as accumulation and agglomeration. Furthermore, once the coating is damaged, a galvanic cell, with graphene as the positive electrode and the metal substrate as the negative electrode, is instantly formed, greatly accelerating the corrosion process. These factors hinder the further application of graphene in the field of corrosion protection.

[0004] In addition, there is the issue of biosorption in the ocean, where the accumulation of biosorbents on surfaces increases surface roughness. Underwater facilities also face corrosion problems, including seawater corrosion and microbial corrosion. Seawater is a corrosive substance; its high oxygen and ion content can cause electrochemical reactions with metal surfaces, leading to corrosion. Microbial corrosion occurs when microorganisms deposit on surfaces, causing localized changes in dissolved oxygen, redox potential, and pH, which enhances the chemical / electrochemical reactions between microorganisms, the medium, and the metal, resulting in or accelerating corrosion of the metal surface.

[0005] Therefore, the research on marine corrosion prevention and biofouling prevention are intertwined issues, and the development and design of high-performance marine anti-corrosion and antifouling coatings is urgently needed. Summary of the Invention

[0006] The purpose of this invention is to address the need for further improvement in the anti-corrosion performance of existing marine anti-corrosion coatings, while simultaneously reducing the adhesion of marine organisms. This invention provides a marine anti-corrosion and antifouling coating and its preparation method. Through formulation design, based on an epoxy-acrylic-polyurethane system and using self-made functional fillers and additives, the invention solves the problems while possessing green and environmentally friendly characteristics.

[0007] To achieve the above objectives, the technical solution adopted by the present invention to solve its technical problems is as follows:

[0008] This invention provides a method for preparing modified graphene fillers, comprising the following steps:

[0009] (1) Oxidation reaction of graphene to prepare graphene oxide;

[0010] (2) Graphene oxide was reacted with tetrabutyl titanate in a solvothermal reaction to prepare nano-titanium modified graphene oxide.

[0011] (3) React nano-titanium modified graphene oxide with silane coupling agent to prepare silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0012] Furthermore, the oxidation reaction is performed using the Hummers oxidation method.

[0013] Furthermore, the amount of graphene oxide and tetrabutyl titanate used is 10-30 mg: 3.0 mL.

[0014] Furthermore, the amount of the nano-titanium modified graphene oxide and the silane coupling agent is 3.5g:0.65-1.0g;

[0015] The silane coupling agent is an aminosilane coupling agent.

[0016] The present invention also provides a method for preparing modified graphene fillers and the modified graphene fillers prepared therefrom.

[0017] This invention provides a method for preparing zwitterionic polymers, comprising:

[0018] A zwitterionic polymer is obtained by copolymerizing an epoxy-containing carbon-carbon double bond with a zwitterionic polymer containing a carbon-carbon double bond.

[0019] Furthermore,

[0020] The ratio of the amount of the epoxy-containing carbon-carbon double bond to the amount of the zwitterion containing the carbon-carbon double bond is 3.0-5.0 mol: 5.0-7.0 mol;

[0021] The epoxy-containing carbon-carbon double bond is glycidyl methacrylate and / or allyl glycidyl ether;

[0022] The zwitterion containing a carbon-carbon double bond is choline and / or betaine containing a carbon-carbon double bond.

[0023] The present invention also provides a method for preparing zwitterionic polymers.

[0024] This invention further provides a marine anti-corrosion and antifouling coating, which is a two-component coating comprising the following raw materials in parts by weight:

[0025] Component A:

[0026] 20-40 parts acrylic resin;

[0027] 5-15 parts epoxy resin;

[0028] 3-6 parts of modified graphene filler;

[0029] 5-10 parts of active metal filler;

[0030] 8-12 parts of zwitterionic polymer;

[0031] 5-10 parts talcum powder;

[0032] Defoamer 0.1-0.3 parts;

[0033] Leveling agent 0.5-1.0 parts;

[0034] 10-20 parts deionized water;

[0035] Component B:

[0036] 15-25 parts of water-based isocyanate curing agent.

[0037] Furthermore,

[0038] The acrylic resin is a water-based hydroxyl acrylic resin with a solid content of 40-45% and a hydroxyl content of 1.5-2.0%.

[0039] Furthermore, the epoxy resin is an aqueous epoxy resin with a solid content of 55-60%.

[0040] Furthermore, the active metal filler is a blend of zinc powder and alumina.

[0041] Furthermore, the zinc powder and alumina are mixed at a mass ratio of 1:0.5-2.0.

[0042] This invention also provides a method for preparing a marine anti-corrosion and antifouling coating, comprising the following steps:

[0043] S1: Add acrylic resin, talc, other additives and some deionized water to the reaction vessel, stir at high speed to mix evenly, then add epoxy resin and continue stirring for 30 minutes to obtain a mixed solution.

[0044] S2: Mix the modified graphene filler, active metal filler and zwitterionic polymer evenly, add the remaining deionized water, and ultrasonically disperse for 30 min to obtain the filler dispersion.

[0045] S3: Add the filler dispersion from S2 to the mixed solution from S1, stir until homogeneous, and obtain component A;

[0046] S4: Add component B to component A of S3, stir continuously until homogeneous, and complete the application within the activation period to obtain a marine anti-corrosion and antifouling coating.

[0047] The present invention has the following beneficial effects:

[0048] (1) This invention provides a marine anti-corrosion and antifouling coating, the main resin of which is a two-component polyurethane structure with epoxy resin, acrylic resin, and isocyanate curing agent as the main components. First, epoxy resin has high polarity, resulting in excellent adhesion to the substrate and good compatibility with fillers and other resins. Second, acrylic resin has excellent weather resistance and gloss and color retention, which can effectively improve the weather resistance of the coating. Third, the polyurethane structure has excellent abrasion resistance and chemical resistance, which can improve the anti-corrosion performance of the coating under extreme marine weather conditions. The epoxy-acrylic-polyurethane system can effectively improve the coating's advantages in adhesion, weather resistance, and anti-corrosion properties.

[0049] (2) This invention provides a marine anti-corrosion and antifouling coating, one of its components being an active metal filler, which is a blend of zinc powder and alumina. Firstly, alumina is an amphoteric oxide that can balance the acidity and alkalinity of the coating surface, placing it in a near-neutral environment and providing initial corrosion protection. Secondly, zinc powder has high oxidizing activity and can act as a sacrificial anode to protect the substrate, further protecting it from corrosion. The synergistic effect of zinc powder and alumina improves the corrosion resistance of the substrate from a chemical protection perspective.

[0050] (3) This invention provides a marine anti-corrosion and antifouling coating, one of its components being a modified graphene filler, which is a self-made silane-modified core-shell structure, wherein the core layer is graphene oxide and the shell layer is a nano-titanium dioxide structure. First, the nano-titanium loaded in the graphene structure greatly increases its specific surface area, effectively enhancing the photocatalytic effect of titanium dioxide and reducing the organic biomass content on the coating surface, thereby achieving an antifouling effect; Second, graphene is a SP 2Hybridized two-dimensional hexagonal honeycomb lattice carbon nanomaterials exhibit a "maze effect," effectively blocking the penetration of chloride ions, water, and oxygen, thus providing highly efficient anti-corrosion performance. Third, the layered structure of graphene has a certain lubricating effect, enhancing the physical properties of the coating. Fourth, once the coating is damaged, the nano-titanium encapsulation of graphene prevents the formation of localized galvanic cells, thereby avoiding electrochemical corrosion. Fifth, graphene's excellent thermal conductivity prevents coating damage caused by extreme temperature fluctuations during use, extending its anti-corrosion lifespan. Sixth, silane modification, especially aminosilane modification, allows modified graphene fillers to exhibit excellent compatibility with epoxy and acrylic resins, improving the mechanical properties of the coating.

[0051] (4) This invention provides a marine anti-corrosion and antifouling coating, one of its components being a zwitterionic polymer, which is a self-made macromolecule containing quaternary ammonium salts and anions. First, zwitterions can form a dense hydration layer with water molecules, effectively preventing the adhesion of proteins and microorganisms, and possessing excellent biofouling resistance; second, the cations in the zwitterions have a quaternary ammonium salt structure, which has certain antimicrobial properties; third, the anions in the zwitterions are phosphates or sulfates, which can coordinate with the substrate to form a complex structure, providing passivation protection for the substrate; fourth, the zwitterionic polymer is a conductive polymer structure that can act as a barrier to prevent ions from penetrating into the substrate, and its excellent ability to conduct electrons and ions can promote the delocalization of surface charges, avoiding the formation of local anodic or cathodic regions that cause localized corrosion; fifth, the ionic groups in the zwitterionic polymer have excellent dispersing effects on resins and fillers, and can be used as macromolecular dispersants.

[0052] Thus, this invention provides a marine anti-corrosion and antifouling coating that provides anti-corrosion treatment from three angles: chemical protection, physical barrier, and substrate passivation, resulting in excellent anti-corrosion effects; at the same time, it provides biofouling protection from two levels: photocatalytic chemistry and zwitterionic physical antifouling, resulting in excellent antifouling performance. Detailed implementation method:

[0053] The present invention will be described in detail below with reference to embodiments. However, it should be understood that the following embodiments are merely illustrative examples of implementation of the present invention and are not intended to limit the scope of the present invention.

[0054] The purpose of this invention is to develop a marine anti-corrosion and antifouling coating. The approach is as follows: First, considering the application potential and existing problems of graphene in the field of corrosion prevention, a graphene filler is prepared by self-making, which is based on graphene, modified with nano-titanium, and modified with silane; simultaneously improving its dispersibility and addressing electrochemical corrosion after damage; concurrently, a polymer with anti-bioadhesion properties is prepared, which can balance the charge of the paint film, further providing corrosion resistance while preventing biofouling; third, given the complexity of the marine environment and the post-biofouling environment, an amphoteric metal filler is compounded with an active metal to achieve initial corrosion prevention. The theoretical basis for this is: graphene is oxidized, then reacted with tetrabutyl titanate in a solvothermal reaction, followed by modification with a silane coupling agent. The amphoteric polymer is prepared by using a common alkaloid as the main component and reducing its hydrophilicity, allowing it to copolymerize with an epoxy group structure. The epoxy group has excellent compatibility with the main resin, and the phosphate or sulfonate structure in the alkaloid can rapidly complex with the metal substrate or metal filler, reducing the corrosion process. The active metal filler can be any commercially available coating material. Within the epoxy-acrylic-polyurethane system, the components work synergistically, providing excellent corrosion and fouling resistance while maintaining physical properties. Examples of this invention are as follows:

[0055] This invention provides a method for preparing modified graphene fillers, comprising the following steps:

[0056] (1) Using the Hummers oxidation method: Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added; the mixture was stirred in an ice bath at 0-5℃ for 3-5 hours; potassium permanganate was added, the temperature was raised to 45℃, and the mixture was stirred until it turned into a paste-like brown color; deionized water A was added and the temperature was raised to 95-100℃ and stirred until the color turned yellow; deionized water B was added and stirred for 1 hour; hydrogen peroxide (30wt%) was added and the mixture was stirred for another 30 minutes; the mixture was filtered, and the insoluble matter was washed three times with deionized water C and then placed in a vacuum dryer at 60℃ for 12 hours to obtain graphene oxide powder;

[0057] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0058] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 170-190℃ for 3-12 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60℃ to constant weight to obtain nano-titanium modified graphene oxide.

[0059] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 10-30 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0060] (3) Mix silane coupling agent and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 9-10 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 3-5 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight to obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0061] The amounts of the silane coupling agent, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 0.65-1.0g:60mL:3mL:3.5g:50mL:50mL;

[0062] The silane coupling agent is an aminosilane coupling agent, which can be KH901, KH902, KH540, KH550, KH602, or KH792; and KH550 is preferred.

[0063] This invention provides a method for preparing zwitterionic polymers, as follows:

[0064] An epoxy-containing carbon-carbon double bond, a zwitterion containing a carbon-carbon double bond, and AIBN were added to 1,4-dioxane. The mixture was heated to 75-85℃ and stirred for 6-10 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60℃ for 6 hours to obtain the zwitterionic polymer.

[0065] The ratio of the amount of the epoxy-containing carbon-carbon double bond to the amount of the zwitterion containing the carbon-carbon double bond is 3.0-5.0 mol: 5.0-7.0 mol;

[0066] The amount of AIBN used is 1.0-1.5% of the total mass of the reactants.

[0067] The epoxy-containing carbon-carbon double bond described in this invention can be glycidyl methacrylate and / or allyl glycidyl ether.

[0068] The zwitterionic ions containing carbon-carbon double bonds mentioned in this invention are choline and / or betaine containing carbon-carbon double bonds.

[0069] The choline containing a carbon-carbon double bond structure can be soybean lecithin, 2-methacryloyloxyethyl phosphoric acid choline, or phosphorylcholine, etc.; and 2-methacryloyloxyethyl phosphoric acid choline is preferred.

[0070] The betaine containing a carbon-carbon double bond structure can be methacrylethyl sulfobetaine or ricinoleic acid propyl betaine, etc.; and methacrylethyl sulfobetaine is preferred.

[0071] This invention further provides a marine anti-corrosion and antifouling coating, which is a two-component coating comprising the following raw materials in parts by weight:

[0072] Component A:

[0073] 20-40 parts acrylic resin;

[0074] 5-15 parts epoxy resin;

[0075] 3-6 parts of modified graphene filler;

[0076] 5-10 parts of active metal filler;

[0077] 8-12 parts of zwitterionic polymer;

[0078] 5-10 parts talcum powder;

[0079] Defoamer 0.1-0.3 parts;

[0080] Leveling agent 0.5-1.0 parts;

[0081] 10-20 parts deionized water;

[0082] Component B:

[0083] 15-25 parts of water-based isocyanate curing agent.

[0084] The acrylic resin described in this invention is a water-based hydroxyl acrylic resin with a solid content of 40-45% and a hydroxyl content of 1.5-2.0%; the acrylic resin described in the following examples of this invention is Uacryl 2120.

[0085] The epoxy resin described in this invention is an aqueous epoxy resin with a solid content of 55-60%; the epoxy resin described in the following examples of this invention is Banco 2360H.

[0086] The active metal filler described in this invention is a blend of zinc powder and alumina.

[0087] The zinc powder and alumina are mixed at a mass ratio of 1:0.5-2.0.

[0088] The talc powder used in this invention is industrial grade and was purchased from Beijing Sanjing Xinde Technology Co., Ltd.

[0089] The defoamer described in this invention is BYK-022 silicone defoamer.

[0090] The leveling agent described in this invention is Tego 440.

[0091] The aqueous isocyanate curing agent described in this invention is OS-9018.

[0092] To better understand the above invention, unless otherwise specified, the method for preparing a marine anti-corrosion and antifouling coating described in the following embodiments of the present invention includes the following steps:

[0093] S1: Add acrylic resin, talc, other additives and some deionized water to the reaction vessel, stir at high speed to mix evenly, then add epoxy resin and continue stirring for 30 minutes to obtain a mixed solution.

[0094] S2: Mix the modified graphene filler, active metal filler and zwitterionic polymer evenly, add the remaining deionized water, and ultrasonically disperse for 30 min to obtain the filler dispersion.

[0095] S3: Add the filler dispersion from S2 to the mixed solution from S1, stir until homogeneous, and obtain component A;

[0096] S4: Add component B to component A of S3, stir continuously until homogeneous, and complete the application within the activation period. Apply the coating to tinplate with a dry film thickness of 70±5μm. After curing at room temperature for 48 hours, a marine anti-corrosion and anti-fouling coating is obtained.

[0097] To further understand the present invention, the following detailed description of a marine anti-corrosion and antifouling coating provided by the present invention is provided in conjunction with embodiments. The scope of protection of the present invention is not limited by the following embodiments.

[0098] Example 1

[0099] A method for preparing modified graphene fillers includes the following steps:

[0100] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 4 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 98°C. The mixture was stirred until it turned into a yellow color. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0101] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0102] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm-1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0103] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 180 °C for 6 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60 °C to constant weight to obtain nano-titanium modified graphene oxide.

[0104] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 20 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0105] Its infrared data is as follows: 3430cm -1 -OH disappears; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH disappears; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists.

[0106] (3) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 10 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 4 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight, and obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0107] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 0.8g:60mL:3mL:3.5g:50mL:50mL.

[0108] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists; 1109 cm⁻¹ -1801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0109] A method for preparing an amphoteric polymer is as follows:

[0110] An epoxy-containing carbon-carbon double bond, 2-methacryloyloxyethyl phosphocholine, and AIBN were added to 1,4-dioxane, and the mixture was heated to 80°C and stirred for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain a zwitterionic polymer.

[0111] The ratio of the epoxy-containing carbon-carbon double bond to 2-methacryloyloxyethyl phosphocholine is 4.0 mol: 6.0 mol;

[0112] The amount of AIBN used is 1.0% of the total mass of the reactants.

[0113] The epoxy-containing carbon-carbon double bond is a mixture of glycidyl methacrylate and allyl glycidyl ether in a molar ratio of 1:2.

[0114] Its infrared data is as follows: 1735cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1187 cm -1 -P=O exists; 1622cm -1 1603cm -1 810cm -1 -C = C- does not exist.

[0115] A marine anti-corrosion and antifouling coating is a two-component coating comprising the following raw materials in parts by weight:

[0116] Component A:

[0117] 30 parts acrylic resin;

[0118] 10 parts epoxy resin;

[0119] 4.5 parts of modified graphene filler;

[0120] 8 parts of active metal filler (zinc powder and alumina mixed at a mass ratio of 1:1.5);

[0121] 10 parts of zwitterionic polymer;

[0122] 6 parts talcum powder;

[0123] 0.2 parts of defoamer;

[0124] 0.8 parts leveling agent;

[0125] 10 parts deionized water;

[0126] Component B:

[0127] 18 parts of water-based isocyanate curing agent.

[0128] Example 2

[0129] A method for preparing modified graphene fillers includes the following steps:

[0130] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 0°C for 5 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 95°C. The mixture was stirred until it turned into a yellow color. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0131] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0132] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0133] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 170 °C for 12 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60 °C to constant weight to obtain nano-titanium modified graphene oxide.

[0134] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 10 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0135] Its infrared data is as follows: 3430cm -1-OH disappears; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH disappears; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists.

[0136] (3) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 9 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 3 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight, and obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0137] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 0.65g:60mL:3mL:3.5g:50mL:50mL.

[0138] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists; 1109 cm⁻¹ -1 801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0139] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0140] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0141] Example 3

[0142] A method for preparing modified graphene fillers includes the following steps:

[0143] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 3 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 100°C. The mixture was stirred until it turned yellow. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0144] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0145] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0146] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 190℃ for 3 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60℃ to constant weight to obtain nano-titanium modified graphene oxide.

[0147] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 30 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0148] Its infrared data is as follows: 3430cm -1 -OH disappears; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH disappears; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists.

[0149] (3) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 10 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 5 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight, and obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0150] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 1.0g:60mL:3mL:3.5g:50mL:50mL.

[0151] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists; 1109 cm⁻¹ -1 801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0152] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0153] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0154] Example 4

[0155] A method for preparing modified graphene fillers includes the following steps:

[0156] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 4 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 98°C. The mixture was stirred until it turned into a yellow color. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0157] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0158] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0159] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 180 °C for 6 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60 °C to constant weight to obtain nano-titanium modified graphene oxide.

[0160] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 10 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0161] Its infrared data is as follows: 3430cm -1 -OH disappears; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH disappears; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists.

[0162] (3) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 10 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 4 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight, and obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0163] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 0.8g:60mL:3mL:3.5g:50mL:50mL.

[0164] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm-1 Ti-O-Ti exists; 1109 cm⁻¹ -1 801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0165] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0166] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0167] Example 5

[0168] A method for preparing modified graphene fillers includes the following steps:

[0169] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 4 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 98°C. The mixture was stirred until it turned into a yellow color. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0170] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0171] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0172] (2) Add graphene oxide powder to anhydrous ethanol A, sonicate for 1 h, add tetrabutyl titanate, stir for 0.5 h, place in a sealed container, and keep warm at 180 °C for 6 h; after the reaction is completed, filter, take the insoluble matter, wash twice with anhydrous ethanol B and deionized water D respectively, and dry the insoluble matter at 60 °C to constant weight to obtain nano-titanium modified graphene oxide.

[0173] The amounts of graphene oxide, anhydrous ethanol A, tetrabutyl titanate, anhydrous ethanol B, and deionized water D are 30 mg: 50 mL: 3.0 mL: 50 mL: 100 mL.

[0174] Its infrared data is as follows: 3430cm -1 -OH disappears; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH disappears; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists.

[0175] (3) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust pH to 10 with ammonia water, add nano-titanium modified graphene oxide, and continue stirring for 4 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, dry the insoluble matter at 60℃ to constant weight, and obtain silanized nano-titanium modified graphene oxide, i.e. modified graphene filler.

[0176] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, nano-titanium modified graphene oxide, deionized water F, and anhydrous ethanol D are 0.8g:60mL:3mL:3.5g:50mL:50mL.

[0177] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 760cm -1 Ti-O-Ti exists; 1109 cm⁻¹ -1 801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0178] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0179] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0180] Example 6

[0181] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0182] A method for preparing an amphoteric polymer is as follows:

[0183] An epoxy-containing carbon-carbon double bond, methacryloylethyl sulfobetaine, and AIBN were added to 1,4-dioxane, and the mixture was heated to 75°C and stirred for 10 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain a zwitterionic polymer.

[0184] The ratio of the epoxy-containing carbon-carbon double bond to methacryloylethyl sulfobetaine is 4.0 mol: 6.0 mol;

[0185] The amount of AIBN used is 1.5% of the total mass of the reactants.

[0186] The epoxy-containing carbon-carbon double bond is a mixture of glycidyl methacrylate and allyl glycidyl ether in a molar ratio of 1:2.

[0187] Its infrared data is as follows: 1735cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1175cm -1 1050cm -1 -S=O exists; 1622cm -1 1603cm -1 810cm -1 -C = C- does not exist.

[0188] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0189] Example 7

[0190] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0191] A method for preparing an amphoteric polymer is as follows:

[0192] Allyl glycidyl ether, a zwitterion containing a carbon-carbon double bond, and AIBN were added to 1,4-dioxane, and the mixture was heated to 85°C and stirred for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain the zwitterionic polymer (M). n =37854, PDI=1.66);

[0193] The ratio of the allyl glycidyl ether to the zwitterion containing a carbon-carbon double bond is 4.0 mol: 6.0 mol;

[0194] The amount of AIBN used is 1.5% of the total mass of the reactants.

[0195] The zwitterion containing carbon-carbon double bonds is a mixture of 2-methacryloyloxyethyl phosphoric acid choline and methacryloylethyl sulfobetaine in a molar ratio of 1:1.

[0196] Its infrared data is as follows: 1735cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1175cm -1 1050cm -1 -S=O exists; 1187cm -1 -P=O exists; 1622cm -1 1603cm -1 810cm -1 -C = C- does not exist.

[0197] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0198] Example 8

[0199] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0200] A method for preparing an amphoteric polymer is as follows:

[0201] An epoxy-containing carbon-carbon double bond, 2-methacryloyloxyethyl phosphocholine, and AIBN were added to 1,4-dioxane, and the mixture was heated to 80°C and stirred for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain a zwitterionic polymer.

[0202] The ratio of the epoxy-containing carbon-carbon double bond to 2-methacryloyloxyethyl phosphocholine is 3.0 mol: 7.0 mol;

[0203] The amount of AIBN used is 1.0% of the total mass of the reactants.

[0204] The epoxy-containing carbon-carbon double bond is a mixture of glycidyl methacrylate and allyl glycidyl ether in a molar ratio of 1:2.

[0205] Its infrared data is as follows: 1735cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1187 cm -1 -P=O exists; 1622cm -11603cm -1 810cm -1 -C = C- does not exist.

[0206] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0207] Example 9

[0208] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0209] A method for preparing an amphoteric polymer is as follows:

[0210] An epoxy-containing carbon-carbon double bond, 2-methacryloyloxyethyl phosphocholine, and AIBN were added to 1,4-dioxane, and the mixture was heated to 80°C and stirred for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain a zwitterionic polymer.

[0211] The ratio of the epoxy-containing carbon-carbon double bond to 2-methacryloyloxyethyl phosphocholine is 5.0 mol: 5.0 mol.

[0212] The amount of AIBN used is 1.0% of the total mass of the reactants.

[0213] The epoxy-containing carbon-carbon double bond is a mixture of glycidyl methacrylate and allyl glycidyl ether in a molar ratio of 1:2.

[0214] Its infrared data is as follows: 1735cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1187 cm -1 -P=O exists; 1622cm -1 1603cm -1 810cm -1 -C = C- does not exist.

[0215] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0216] Example 10

[0217] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0218] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0219] A marine anti-corrosion and antifouling coating is a two-component coating comprising the following raw materials in parts by weight:

[0220] Component A:

[0221] 20 parts acrylic resin;

[0222] 5 parts epoxy resin;

[0223] Three parts of modified graphene filler;

[0224] Five parts of active metal filler (a mixture of zinc powder and alumina at a mass ratio of 1:1.5);

[0225] Eight parts of zwitterionic polymer;

[0226] 5 parts talcum powder;

[0227] 0.1 parts of defoamer;

[0228] 0.5 parts leveling agent;

[0229] 15 parts deionized water;

[0230] Component B:

[0231] 15 parts of water-based isocyanate curing agent.

[0232] Example 11

[0233] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0234] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0235] A marine anti-corrosion and antifouling coating is a two-component coating comprising the following raw materials in parts by weight:

[0236] Component A:

[0237] 40 parts acrylic resin;

[0238] 15 parts epoxy resin;

[0239] Six parts of modified graphene filler;

[0240] 10 parts of active metal filler (zinc powder and alumina mixed at a mass ratio of 1:1.5);

[0241] 12 parts of zwitterionic polymer;

[0242] 10 parts talcum powder;

[0243] 0.3 parts of defoamer;

[0244] Leveling agent 1.0 part;

[0245] 20 parts deionized water;

[0246] Component B:

[0247] 25 parts of water-based isocyanate curing agent.

[0248] Example 12

[0249] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0250] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0251] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that zinc powder and alumina are mixed at a mass ratio of 1:0.5.

[0252] Example 13

[0253] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0254] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0255] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that zinc powder and alumina are mixed in a 1:1 mass ratio.

[0256] Example 14

[0257] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0258] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0259] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that zinc powder and alumina are mixed in a mass ratio of 1:2.

[0260] The following comparative examples are all compared with specific Example 1:

[0261] Comparative Example 1

[0262] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0263] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that no modified graphene filler is added to component A.

[0264] Comparative Example 2

[0265] A method for preparing modified graphene fillers includes the following steps:

[0266] Graphite powder and sodium nitrate were loaded into a reactor, and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 4 hours. Potassium permanganate was added, and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 98°C. The mixture was stirred until it turned yellow. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for another 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then dried under vacuum at 60°C for 12 hours to obtain graphene oxide powder.

[0267] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0268] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm -1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0269] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0270] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0271] Implement Comparative Example 3

[0272] A method for preparing modified graphene fillers includes the following steps:

[0273] (1) Graphite powder and sodium nitrate were loaded into a reactor and concentrated sulfuric acid was added. The mixture was stirred in an ice bath at 5°C for 4 hours. Potassium permanganate was added and the temperature was raised to 45°C. The mixture was stirred until it turned into a brown paste. Deionized water A was added and the temperature was raised to 98°C. The mixture was stirred until it turned into a yellow color. Deionized water B was added and stirred for 1 hour. Hydrogen peroxide (30 wt%) was added and the mixture was stirred for 30 minutes. The mixture was filtered, and the insoluble matter was washed three times with deionized water C. The mixture was then placed in a vacuum dryer at 60°C for 12 hours to obtain graphene oxide powder.

[0274] The ratio of the amounts of graphite powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water A, deionized water B, hydrogen peroxide, and deionized water C is 1g:0.5g:50mL:3g:50mL:200mL:10mL:150mL.

[0275] Its infrared data is as follows: 3430cm -1 -OH is present; 1720cm-1 -C=O exists; 3445cm -1 1734cm -1 -COOH is present; 1220cm -1 1105cm -1 Epoxy groups are present.

[0276] (2) After mixing silane coupling agent KH550 and anhydrous ethanol C, sonicate for 30 min, add deionized water E, continue stirring for 30 min, adjust the pH to 10 with ammonia water, add graphene oxide, and continue stirring for 4 h; after the reaction is completed, filter, wash the insoluble matter twice with deionized water F and anhydrous ethanol D, and dry the insoluble matter at 60 °C to constant weight to obtain silanized graphene oxide, i.e. modified graphene filler.

[0277] The amounts of the silane coupling agent KH550, anhydrous ethanol C, deionized water E, graphene oxide, deionized water F, and anhydrous ethanol D are 0.8g:60mL:3mL:3.5g:50mL:50mL.

[0278] Its infrared data is as follows: 1720cm -1 -C=O exists; 1220cm -1 1105cm -1 Epoxy groups are present; 1109 cm -1 801cm -1 -Si-O- exists; 2928cm -1 -CH exists; 1560cm -1 -NH exists.

[0279] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0280] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0281] Comparative Example 4

[0282] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0283] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that zwitterionic polymers are not added to component A.

[0284] Comparative Example 5

[0285] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0286] A method for preparing an amphoteric polymer is as follows:

[0287] 2-Methacryloxyethylphosphocholine and AIBN were added to 1,4-dioxane, and the mixture was heated to 80°C and stirred for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, filtered, and the filtrate was collected, distilled under reduced pressure, and dried under vacuum at 60°C for 6 hours to obtain the zwitterionic polymer. PDI = 1.44);

[0288] The amount of AIBN used is 1.0% of the total mass of the reactants.

[0289] Its infrared data is as follows: 1735cm -1 -C=O exists; 1187cm -1 -P=O exists; 1603cm -1 810cm -1 -C = C- does not exist.

[0290] A marine anti-corrosion and antifouling coating is a two-component coating, and its components are the same as those in Specific Example 1.

[0291] Comparative Example 6

[0292] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0293] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0294] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that no active metal filler is added to component A.

[0295] Comparative Example 7

[0296] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0297] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0298] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that the active metal filler in component A is zinc powder.

[0299] Implemented Comparative Example 8

[0300] A method for preparing a modified graphene filler is the same as in Specific Example 1.

[0301] The preparation method of an amphoteric polymer is the same as in Specific Example 1.

[0302] A marine anti-corrosion and antifouling coating is a two-component coating, with the same components as in Specific Example 1. The difference is that the active metal filler in component A is alumina.

[0303] The physical properties of the marine anti-corrosion and antifouling coatings prepared in Examples 1-14 and Comparative Examples 1-8 of the present invention were measured respectively, and the results are shown in Table 1.

[0304] Table 1 Physical test performance of each embodiment

[0305]

[0306] First, compared with Comparative Examples 1-8, the marine anti-corrosion and antifouling coating of the present invention has excellent corrosion resistance and biofouling resistance, as well as excellent physical properties.

[0307] Secondly, as can be observed from Example 1 and Comparative Examples 1-3, the modified graphene filler in the marine anti-corrosion and antifouling coating of the present invention, modified with nano-titanium and modified with silane coupling agent, has excellent dispersibility. At the same time, due to the "maze effect" brought about by the graphene sheet structure, it has excellent anti-corrosion properties. In addition, the graphene modified with nano-titanium will not form local galvanic cells for electrochemical corrosion after the coating is damaged, and has excellent long-term anti-corrosion performance. As can be observed from Example 1 and Comparative Examples 4-5, the zwitterionic polymer acts as a dispersant, making the fillers disperse evenly and improving mechanical properties. At the same time, the phosphate ester structure has an anchoring and complexing effect on the substrate, improving the anti-corrosion performance. On the other hand, the zwitterionic polymer formed by zwitterionic self-polymerization has a large hydrophilicity, which has a significant impact on the anti-corrosion performance of the paint film. As can be observed from Example 1 and Comparative Examples 6-8, the zinc powder and alumina in the active metal filler have good synergistic anti-corrosion performance.

[0308] Third, it can be observed from Example 1 and Comparative Examples 1-5 that the nano-titanium structure and zwitterionic polymer in the marine anti-corrosion and antifouling coating of the present invention have synergistic biofouling resistance.

[0309] In summary, the marine anti-corrosion and antifouling coating of the present invention has excellent anti-corrosion and biofouling properties.

[0310] The testing method is as follows:

[0311] (1) Hardness: Tested according to the method described in GB / T 6739-2022. Mitsubishi pencil and 750g weight were used.

[0312] (2) Adhesion: Adhesion test shall be conducted in accordance with the method described in GB / T 9286-2021.

[0313] (3) Impact resistance: Tested according to the method described in GB / T 1732-2020.

[0314] (4) Resistance to neutral salt spray: Tested according to the method described in GB / T 1771-2007. The method of expressing resistance to neutral salt spray is divided into the following categories according to the severity of corrosion: no defects, blistering, paint film peeling, rust spots, and corrosion.

[0315] (5) Salt water resistance: Prepare a 5wt% NaCl aqueous solution, immerse the sample to be tested in it, and observe the changes in the paint film after 25℃ for 1000h and 25℃ for 1200h respectively. Salt water resistance is expressed according to the severity of corrosion as follows: no defects, blistering, paint film peeling, rust spots, and corrosion.

[0316] (6) Anti-cell adhesion: 3T3 mouse embryonic bromide blastocytes were preserved in T-75 Falcon cell culture and cultured in sterile Durbeco modified Falcon medium (DMEM) containing 10% fetal bovine serum (FBS) and 100 units / ml penicillin and 0.1 mg / ml streptomycin. Six samples of each cover (36 samples in total) were placed in 6-well tissue culture plates and irradiated under UV light for 10–15 min. Cells were seeded onto the varnish at a density of approximately 11,000 cells / cm². The cells were then incubated at 37°C and 5% CO2 for 24 h, after which the medium was poured off and the cells were gently rinsed once with PBS. The number of adherent cells was defined as the number of viable cells per 100*field. The control percentage was calculated by multiplying the percentage of viable cells on the treated substrate to the percentage of viable cells on the untreated substrate by 100. The mean control adhesion rate for each sample group was determined, and the viability assays were statistically compared as described above.

[0317] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A marine antifouling coating, characterized in that: A two-component coating, comprising the following raw materials in parts by weight: Component A: acrylic resin 20-40 parts; epoxy resin 5-15 parts; modified graphene filler 3-6 parts; active metal filler 5-10 parts; zwitterionic polymer 8-12 parts; talc 5-10 parts; defoamer 0.1-0.3 parts; leveling agent 0.5-1.0 parts; deionized water 10-20 parts; Component B: waterborne isocyanate curing agent 15-25 parts; wherein the preparation method of the modified graphene filler comprises the following steps: (1) graphene oxidation reaction to prepare graphene oxide; (2) solvothermal reaction of graphene oxide and tetrabutyl titanate to prepare nano titanium modified graphene oxide; (3) reaction of nano titanium modified graphene oxide and silane coupling agent to prepare silanized nano titanium modified graphene oxide, i.e. modified graphene filler; wherein the preparation method of the zwitterionic polymer is as follows: copolymerization of carbon-carbon double bond containing epoxy group and zwitterionic polymer containing carbon-carbon double bond to obtain zwitterionic polymer; the use amount ratio of the carbon-carbon double bond containing epoxy group and the zwitterionic polymer containing carbon-carbon double bond is 3.0-5.0 mol:5.0-7.0 mol; the carbon-carbon double bond containing epoxy group is glycidyl methacrylate and / or allyl glycidyl ether; the zwitterionic polymer containing carbon-carbon double bond is choline containing carbon-carbon double bond structure and / or betaine containing carbon-carbon double bond structure.

2. The marine corrosion and antifouling coating according to claim 1, characterized in that: the oxidation reaction adopts Hummers oxidation method.

3. The marine corrosion and antifouling coating according to claim 1, characterized in that: the use amount of the graphene oxide and tetrabutyl titanate is 10-30 mg:3.0 mL.

4. The marine corrosion and antifouling coating according to claim 1, characterized in that: the use amount of the nano titanium modified graphene oxide and silane coupling agent is 3.5 g:0.65-1.0 g; the silane coupling agent is amino silane coupling agent.

5. An anticorrosive antifouling coating for marine use according to claim 1, characterized in that: the acrylic resin is waterborne hydroxyl acrylic resin with solid content of 40-45% and hydroxyl content of 1.5-2.0%.

6. An anticorrosive antifouling coating for marine use according to claim 1, characterized in that: the epoxy resin is waterborne epoxy resin with solid content of 55-60%.

7. An anticorrosive antifouling coating for marine use according to claim 1, characterized in that: the active metal filler is a blend of zinc powder and aluminum oxide.

8. An anticorrosive antifouling coating for marine use according to claim 7, characterized in that: the zinc powder and aluminum oxide are mixed in a mass ratio of 1:0.5-2.

0.

9. A process for the preparation of a marine anticorrosive antifouling coating as claimed in claim 1, characterized in that: comprising the following steps: S1: add acrylic resin, talc, other additives and part of deionized water in a reaction container, mix uniformly under high-speed stirring, then add epoxy resin, continue to stir for 30 min to obtain a mixed solution; S2: mix the modified graphene filler, active metal filler and zwitterionic polymer uniformly, add the remaining deionized water and ultrasonic dispersion for 30 min to obtain a filler dispersion liquid; S3: add the filler dispersion liquid in S2 to the mixed solution in S1, stir uniformly to obtain component A; S4: add component B to component A in S3, stir uniformly and then apply within the activation period to obtain the marine corrosion and antifouling coating.

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