Rust-in-rust anticorrosive coating and method for preparing the same

Abstract

The application provides a rust-bearing rust-converting anticorrosive coating and a preparation method thereof. The rust-bearing rust-converting anticorrosive coating is composed of the following components: water 20-60 parts by weight; water-based epoxy resin 25-40; surfactant 10-12 parts by weight; filler 5-12 parts by weight; rust-converting agent 0.3-0.6 parts by weight; curing agent 10-15 parts by weight; pigment 1-5 parts by weight; rust-converting stabilizer 0.2-0.4 parts by weight; defoaming agent 0.5-0.7; thickening agent 1-2.5 parts by weight; and the rust-converting stabilizer is zinc phosphate and oleic acid modified triazine-based covalent organic framework material with a weight ratio of 1:0.3-0.7. The preparation method comprises the steps of triazine-based covalent organic framework material preparation, oleic acid modified triazine-based covalent organic framework material preparation, dispersion liquid formation and mixing of the dispersion liquid and the remaining components. The rust-bearing rust-converting anticorrosive coating is prepared, and the anticorrosive performance on the surface of the steel structure is greatly improved.

Description

Technical Field

[0001] This application relates to the field of chemical and materials production equipment technology, and in particular to a rust-reversing anti-corrosion coating and its preparation method. Background Technology

[0002] Metal corrosion is the phenomenon where metals are damaged by the chemical or electrochemical action of environmental media. Metal corrosion is prevalent across various industries and causes significant economic losses annually. Applying anti-corrosion coatings to metal surfaces is one of the primary measures for metal corrosion prevention.

[0003] Traditional anti-rust coatings cannot be applied directly to rusted metal surfaces. Thorough rust removal is required before coating. However, when the equipment is large, complex, and the construction conditions are harsh, it is difficult to use mechanized methods for rust removal. Manual grinding is necessary, which is not only labor-intensive and inefficient, but also very costly.

[0004] Rust-resistant anti-rust coatings are applied directly to corroded metal surfaces. They stabilize, passivate, or transform the rust, turning reactive rust into a harmless substance, thus achieving the dual purpose of rust removal and protection. This significantly improves the efficiency of anti-corrosion coating application. However, in existing technologies, the adhesion between rust-resistant anti-rust coatings and metal surfaces is insufficient, resulting in low adhesion and subsequent coating peeling, reduced anti-corrosion performance, increased frequency of repainting and equipment replacement, and ultimately, higher costs for businesses. Summary of the Invention

[0005] This application provides a rust-reversing anti-corrosion coating and its preparation method to solve the problems mentioned in the background art.

[0006] On the one hand, this application provides a rust-to-rust anti-corrosion coating, which, by weight, comprises the following components: Water: 20-60 parts by weight; Waterborne epoxy resin: 25-40 parts by weight; Surfactant: 10-12 parts by weight; Filler: 5-12 parts by weight; Rust remover: 0.3-0.6 parts by weight; Hardener: 10-15 parts by weight; Pigment: 1-5 parts by weight; Rust stabilizer: 0.2-0.4 parts by weight; Defoamer: 0.5-0.7 parts by weight; Thickener: 1-2.5 parts by weight; The rust stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.3-0.7.

[0007] Optionally, the surfactant may be coconut oil diethanolamide or dodecyl dimethyl betaine.

[0008] Optionally, the filler may be one or more of graphene, molybdenum disulfide, mica, and boron nitride.

[0009] Optionally, the particle size of graphene, molybdenum disulfide, mica, and boron nitride is 10-100 nm.

[0010] Optionally, the rust remover may be one or more of hydrochloric acid, phytic acid, salicylic acid, tannic acid, ascorbic acid, and oxalic acid.

[0011] Optionally, the pigment may be one of titanium dioxide, zinc barium white, zinc oxide, antimony oxide, iron oxide red, hydrated iron yellow, or iron black.

[0012] Optionally, the defoamer is one or more of BYK011, BYK012, and BYK024.

[0013] Optionally, the thickener may be any one of polyacrylate, hydroxymethyl cellulose, and agar.

[0014] On the other hand, this application provides a method for preparing a rust-to-rust anti-corrosion coating, which includes the following steps: (1) Preparation of triazine-based covalent organic framework materials: 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was placed in an oil bath at 110-140℃ and reacted for 12-24 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of the triazine-based covalent organic framework material. The preliminary product of the triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material.

[0015] The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1-1.5:20-25:35-40:25-28.

[0016] (2) Preparation of oleic acid modified triazine covalent organic framework material: Triazine covalent organic framework material and oleic acid are dispersed in anhydrous ethanol and ultrasonically treated for 10-35 min to form triazine covalent organic framework material dispersion and oleic acid dispersion. The triazine covalent organic framework material dispersion and oleic acid dispersion are mixed and ultrasonically treated at a temperature of 30-45℃ to obtain modified triazine covalent organic framework material mixture. The solid is separated by centrifugation and washed with anhydrous ethanol at least 3 times to obtain oleic acid modified triazine covalent organic framework material.

[0017] (3) Add waterborne epoxy resin, surfactant, rust remover, rust remover stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion.

[0018] (4) Add filler, curing agent, pigment, thickener and defoamer to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0019] Optionally, the preparation steps of oleic acid modified triazine covalent organic framework material further include: the weight ratio of oleic acid to triazine covalent organic framework material is 1.5-3:1, the weight-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:10-20mL, and the weight-volume ratio of triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:20-45mL.

[0020] The rust-to-rust anti-corrosion coating and its preparation method provided in this application realize the preparation of the rust-to-rust anti-corrosion coating, improve the stability of the bonding between the anti-corrosion coating and the steel structure surface, and thus greatly improve the anti-corrosion performance of the steel structure surface. Compared with the prior art, it has the following beneficial effects: (1) By using water-based epoxy resin as the base resin and the main film-forming substance, a protective film can be formed on the surface of metal equipment after curing, thus achieving corrosion protection of the metal surface. By adding a rust-reducing agent, a chemical reaction occurs with rust, and the resulting stable complex firmly covers the steel surface, achieving the purpose of rust prevention. By adding a rust-reducing stabilizer, a further complex is formed with the steel structure substrate surface, improving the bonding force between the anti-corrosion coating and the steel structure surface. The rust-reducing stabilizer is a zinc phosphate and oleic acid modified triazine covalent organic framework material. Zinc phosphate is tightly bound to metal ions, and the oleic acid modified triazine covalent organic framework material reacts with the metal to generate a metal complex, improving the bonding force with the steel structure surface. At the same time, it works synergistically with the rust-reducing agent to promote the stability of the bonding between the rust-reducing agent and the steel structure surface. This improves the stability and corrosion resistance of the anti-corrosion coating. Furthermore, by grafting oleic acid onto the triazine-based covalent organic framework material, the presence of carboxyl groups can promote the bonding stability between the rust stabilizer and the steel structure surface. The presence of long-chain alkanes in oleic acid is hydrophobic, which is beneficial for the anti-corrosion coating to have a good shielding effect against external water and water vapor after the coating is applied. This greatly reduces the chemical and / or electrochemical corrosion caused by water wetting of the anti-corrosion coating. While improving the stable bonding between the steel structure surface and the anti-corrosion coating, it also shields against the erosion of external corrosive media. Under the dual effect, the anti-corrosion performance of the anti-corrosion coating is significantly improved.

[0021] (2) The graphene, molybdenum disulfide, mica, and boron nitride in the filler have a particle size of 50-100 nm and belong to a layered structure. They can not only form a maze effect, increasing the path of corrosive ions to penetrate the coating and increasing the barrier performance of the coating, but also improve the mechanical strength of the coating on the metal surface and adjust the apparent density of the coating. This allows the filler and water-based epoxy resin to work synergistically to improve the density of the coating film after it is formed, which has a positive promoting effect on isolating corrosive media.

[0022] (3) The operation method of this application is simple, low-cost, universal, and easy to scale up.

[0023] (4) This application can be used not only to remove rust and prevent rust on rusted steel, but also to prevent rust on rust-free steel surfaces. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1This is a flowchart illustrating the preparation process of a rust-converting anti-corrosion coating provided in one embodiment of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are also within the scope of protection of this application.

[0027] On the one hand, this application provides a rust-to-rust anti-corrosion coating, which, by weight, comprises the following components: Water: 20-60 parts by weight; Waterborne epoxy resin: 25-40 parts by weight; Surfactant: 10-12 parts by weight; Filler: 5-12 parts by weight; Rust remover: 0.3-0.6 parts by weight; Hardener: 10-15 parts by weight; Pigment: 1-5 parts by weight; Rust stabilizer: 0.2-0.4 parts by weight; Defoamer: 0.5-0.7 parts by weight; Thickener: 1-2.5 parts by weight; The rust stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.3-0.7.

[0028] Specifically, this application uses waterborne epoxy resin as the base resin and main film-forming substance. After curing, it can form a protective film on the surface of metal equipment, isolating the metal surface from the atmosphere. This prevents direct contact between the metal and oxygen, moisture, or solvents in the air, thus achieving corrosion protection. The metal equipment is steel, aluminum, or other metals or alloys. The addition of surfactants improves the dispersibility and dispersion stability of the components in the coating, ensuring uniform dispersion of the components on the metal surface during application, thus improving coating uniformity and enhancing the coating's corrosion resistance. Fillers increase the coating's hardness and wear resistance, and work together with the waterborne epoxy resin to improve film density, further enhancing corrosion resistance.

[0029] Rust-reducing agents react chemically with rust, transforming harmful rust into protective complexes or chelates. This transformation not only removes the rust but also forms stable complexes that firmly coat the steel surface, effectively preventing contact between the steel and air, thus achieving rust prevention. Rust-reducing agents can fully wet and penetrate the rust layer, converting harmful corrosion products (such as Fe2O3 and other impurities) into stable, harmless coatings (such as Fe3O4) that adhere to the steel surface, further enhancing the coating's corrosion resistance. By using rust-reducing agents, the complex process of grinding and rust removal on the steel structure surface before coating is avoided, improving coating efficiency and significantly reducing construction intensity and coating costs.

[0030] Rust-converting stabilizers are used after coating to further form complexes with the steel structure substrate surface. Working synergistically with the rust-converting agent, they enhance the adhesion between the anti-corrosion coating and the steel structure surface, while simultaneously deactivating the steel surface, making it difficult to react with other substances such as oxygen and water in the air. In this application, the rust-converting stabilizer is a zinc phosphate and oleic acid-modified triazine-based covalent organic framework material in a weight ratio of 1:0.3-0.7. Zinc phosphate can tightly bind with metal ions, forming insoluble precipitates, thereby effectively preventing the oxidation and corrosion of metal ions, significantly improving the rust-preventive performance of the coating, increasing the coating's adhesion and coverage area, forming a robust protective film, effectively resisting the erosion of the coating by humidity, oxygen, and polluted environments, significantly improving the coating's anti-corrosion performance and extending its service life. Oleic acid-modified triazine-based covalent organic framework materials contain C=C, C=O, NH, and -CH groups that can react with metals. This allows the oleic acid-modified triazine-based covalent organic framework material to react with the steel structure substrate surface, forming metal complexes and improving the bonding with the steel structure surface. Simultaneously, it works synergistically with rust-reducing agents to promote the stability of the bonding between the rust-reducing agent and the steel structure surface, thereby improving the stability and corrosion resistance of the anti-corrosion coating. Furthermore, by grafting oleic acid onto the triazine-based covalent organic framework material, the presence of oleic acid carboxyl groups promotes the bonding stability of the rust-reducing stabilizer with the steel structure surface. On the other hand, oleic acid contains long-chain alkanes, which are hydrophobic, providing a good barrier against water and water vapor after the anti-corrosion coating has formed. This significantly reduces the chemical and / or electrochemical corrosion caused by water wetting of the anti-corrosion coating. While improving the stable bonding between the steel structure surface and the anti-corrosion coating, it also shields against external corrosive media. This dual effect significantly improves the anti-corrosion performance of the coating.

[0031] Hardeners are used to accelerate the curing of the coating after application, forming a protective layer. Pigments are used to color the anti-corrosion coating according to the equipment requirements, selecting appropriate colors. Defoamers eliminate foam generated during the mixing or application of the anti-corrosion coating, improving the smoothness of the film after coating formation and thus enhancing its anti-corrosion performance. Thickeners adjust the viscosity of the anti-corrosion coating to suit the surfaces of steel structures in different environments.

[0032] Furthermore, the rust-reversing stabilizer also includes 1,4-diaminoanthraquinone, with a weight ratio of 1,4-diaminoanthraquinone to zinc phosphate of 0.03-0.08:1. 1,4-diaminoanthraquinone contains anthraquinone groups, and its molecule contains multiple benzene rings interconnected through a conjugated system, forming a π-bond conjugated system. Simultaneously, amino groups are attached to the anthraquinone group. Through the activation of the steel structure surface and rust by the rust-reversing agent, the nitrogen atoms in the amino groups can coordinate with the external electrons generated on the steel structure surface, resulting in strong adhesion between 1,4-diaminoanthraquinone and the steel structure surface. At the same time, the π-bond conjugated system of the anthraquinone group has excellent stability, promoting the stability between the rust-reversing stabilizer and the steel structure surface. Furthermore, it synergistically works with zinc phosphate and oleic acid-modified triazine-based covalent organic framework materials to improve the stability of the adhesion between the anti-corrosion coating and the steel structure surface.

[0033] Furthermore, the rust-to-rust anti-corrosion coating provided in this application also includes 1-3 parts by weight of dispersant and 1-2 parts by weight of anti-settling agent. The dispersant can improve the dispersibility of each component in the coating, which helps to improve the uniformity of the coating. The anti-settling agent can prevent the sedimentation of each component in the coating and improve the anti-sagging performance of the coating. The dispersant is purchased from BYK190 of BYK Chemie GmbH, Germany, and the anti-settling agent is purchased from BYK-410 of BYK Chemie GmbH, Germany.

[0034] This application, through the aforementioned scheme, improves the stability of the bonding between the anti-corrosion coating and the steel structure surface, enhances the adhesion between the anti-corrosion coating and the steel structure surface, and thus significantly improves the anti-corrosion performance of the steel structure surface. By using water-based epoxy resin as the base resin and the main film-forming substance, a protective film can be formed on the surface of metal equipment after curing, achieving anti-corrosion of the metal surface. By adding a rust-reversing agent, a chemical reaction occurs with rust, converting harmful rust into a protective complex or chelate. Moreover, the formed stable complex firmly covers the steel surface, blocking the contact between the steel and air, achieving the purpose of rust prevention. By adding a rust-reversing stabilizer, a further complex is formed with the steel structure substrate surface, and it works synergistically with the rust-reversing agent to improve the adhesion between the anti-corrosion coating and the steel structure surface. The rust-reversing stabilizer is a zinc phosphate and oleic acid modified triazine-based covalent organic framework material. Zinc phosphate can bind tightly with metal ions to form insoluble precipitates. Oleic acid-modified triazine-based covalent organic framework materials react with metals to form metal complexes, improving adhesion to the steel structure surface. Simultaneously, it works synergistically with rust-reducing agents to promote the stability of the bond between the rust-reducing agent and the steel structure surface. This, in turn, improves the stability and corrosion resistance of the anti-corrosion coating. Furthermore, by grafting oleic acid onto the triazine-based covalent organic framework material, the presence of oleic acid carboxyl groups promotes the stability of the bond between the rust-reducing stabilizer and the steel structure surface. Additionally, oleic acid contains long-chain alkanes, which are hydrophobic, providing a good barrier against water and water vapor after the anti-corrosion coating has formed. This significantly reduces chemical and / or electrochemical corrosion caused by water wetting of the anti-corrosion coating. While improving the stable bond between the steel structure surface and the anti-corrosion coating, it also shields against external corrosive media. This dual effect significantly improves the anti-corrosion performance of the coating and reduces production costs.

[0035] Optionally, the surfactant may be coconut oil diethanolamide or dodecyl dimethyl betaine.

[0036] Specifically, coconut oil diethanolamide or dodecyl dimethyl betaine can reduce the surface energy of each component in the coating, improve the dispersibility of the coating, and thus promote the uniformity of the coating during application. This allows each component to play its full role and ensures the anti-corrosion performance of the anti-corrosion coating.

[0037] Optionally, the filler may be one or more of graphene, molybdenum disulfide, mica, and boron nitride.

[0038] Specifically, graphene, molybdenum disulfide, mica, and boron nitride all possess layered structures, which not only create a labyrinth effect, increasing the pathways for corrosive ions to penetrate the coating and enhancing its barrier properties, but also improve the mechanical strength of the coating on the metal surface, adjust the apparent density of the coating, and enable the filler and water-based epoxy resin to work synergistically to improve the density of the coating film, thus positively promoting the isolation of corrosive media.

[0039] Optionally, the particle size of graphene, molybdenum disulfide, mica, and boron nitride is 10-100 nm.

[0040] Specifically, smaller particle sizes can more easily fill the rust on the surface of steel structures, and work synergistically with water-based epoxy resin to form a denser protective film on the surface of the steel structure. This increases the path for corrosive ions to penetrate the coating, enhances the barrier properties of the coating, and isolates external corrosive media.

[0041] Optionally, the rust remover may be one or more of hydrochloric acid, phytic acid, salicylic acid, tannic acid, ascorbic acid, and oxalic acid.

[0042] Specifically, steel structures easily absorb oxygen, moisture, and other corrosive media from the air, leading to rust. The rust products are mainly compounds of ferric and ferrous iron, with a loose and unstable structure. Rust-removing agents are inorganic acid salts, organic acids, or mixtures of both. They passivate or transform the active and harmful iron compounds in the rust layer into harmless and stable coatings. Simultaneously, they chelate with the rust, forming a complex film with strong adhesion to the steel structure surface, achieving both rust removal and corrosion prevention.

[0043] The mass percentage of hydrochloric acid is 5-10%.

[0044] Optionally, the pigment may be one of titanium dioxide, zinc barium white, zinc oxide, antimony oxide, iron oxide red, hydrated iron yellow, or iron black.

[0045] Specifically, pigments are used to color anti-corrosion coatings and are added as needed in actual working conditions.

[0046] Optionally, the defoamer is one or more of BYK011, BYK012, and BYK024, all of which are purchased from BYK Chemical GmbH, Germany.

[0047] Optionally, the thickener may be any one of polyacrylate, hydroxymethyl cellulose, and agar.

[0048] On the other hand, such as Figure 1 As shown, this application provides a method for preparing a rust-to-rust anti-corrosion coating, which includes the following steps: (1) Preparation of triazine-based covalent organic framework materials: 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was then placed in an oil bath at 110-140℃ and reacted for 12-24 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1-1.5:20-25:35-40:25-28; (2) Preparation of oleic acid modified triazine covalent organic framework material: Triazine covalent organic framework material and oleic acid are dispersed in anhydrous ethanol and ultrasonically treated for 10-35 min to form triazine covalent organic framework material dispersion and oleic acid dispersion. The triazine covalent organic framework material dispersion and oleic acid dispersion are mixed and ultrasonically treated at a temperature of 30-45℃ to obtain modified triazine covalent organic framework material mixture. The solid is separated by centrifugation and washed with anhydrous ethanol at least 3 times to obtain oleic acid modified triazine covalent organic framework material. (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; (4) Add filler, curing agent, pigment, thickener and defoamer to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0049] Specifically, at room temperature, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine and 1,3,5-tris(4-formylphenyl)benzene are dispersed in mesitylene, 1,4-dioxane, and acetic acid to form a mixed solution. This solution is then transferred to an oil bath at 110-140°C and reacted for 12-24 hours. This allows the amino groups on the 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to react with the 1,3,5-tris(4-formylphenyl)benzene, generating a triazine-based covalent organic framework material containing C=C, C=O, NH, and -CH groups. This framework can react with the metal on the steel structure surface to form a metal complex, improving the bonding stability with the steel structure surface. Room temperature refers to 20-35°C. Oleic acid was grafted onto a triazine-based covalent organic framework material by ultrasonic treatment at 30-45℃. One end of the oleic acid was connected to the triazine-based covalent organic framework material, while the other end was a long-chain alkyl group, thus improving the hydrophobicity of the anti-corrosion coating. During the modification process, the triazine-based covalent organic framework material and oleic acid were separately dispersed in anhydrous ethanol and then ultrasonically dispersed, resulting in more uniform dispersion and thus improving the degree of modification of the triazine-based covalent organic framework material. The high degree of reaction between oleic acid and the triazine-based covalent organic framework material further enhanced the anti-corrosion performance of the coating.

[0050] Optionally, the preparation steps of oleic acid modified triazine covalent organic framework material further include: washing the modified triazine covalent organic framework material mixture and then vacuum drying it to obtain oleic acid modified triazine covalent organic framework material.

[0051] Specifically, drying improves the purity of the oleic acid-modified triazine-based covalent organic framework material, facilitating its mixing with other components and simplifying metering during addition. Vacuum drying is performed in a vacuum drying oven at 120-140°C for 10-14 hours, with a vacuum level of 0.01 Pa to 10 Pa.

[0052] Optionally, the weight ratio of oleic acid to triazine covalent organic framework material is 1.5-3:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:10-20mL, and the weight-to-volume ratio of triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:20-45mL.

[0053] Specifically, the higher amount of oleic acid compared to the triazine-based covalent organic framework material facilitates more complete grafting of oleic acid onto the triazine-based covalent organic framework material. Increasing the amount of oleic acid allows it to synergistically work with the rust-transfer agent, promoting the bonding of the modified triazine-based covalent organic framework material to the steel structure surface, improving the adhesion of the anti-corrosion coating. Simultaneously, oleic acid enhances the hydrophobicity of the anti-corrosion coating, thereby improving its anti-corrosion performance. Controlling the amount of anhydrous ethanol not only improves the uniformity of the oleic acid dispersion and the triazine-based covalent organic framework material dispersion but also increases the degree of reaction during oleic acid modification.

[0054] In the oleic acid dispersion and the triazine covalent organic framework material dispersion, the weight-volume ratio of oleic acid and triazine covalent organic framework material to anhydrous ethanol only represents a proportional relationship and is not limited to the specific values ​​mentioned above. In actual working conditions, this ratio can be scaled up or down according to the amount of reactants.

[0055] The rust-converting anti-corrosion coating provided in this application can be applied by brushing, rolling, or spraying, with the coating thickness determined according to the actual working conditions. If multiple layers are required, the next layer should be applied only after the previous one has dried.

[0056] The present invention will be further described in detail below with reference to embodiments. However, it should be understood that the embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0057] Example 1

[0058] A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: (1) Preparation of triazine-based covalent organic framework materials: At room temperature, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was then placed in an oil bath at 110°C and reacted for 12-24 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1:20:35:25; (2) Preparation of oleic acid-modified triazine-based covalent organic framework material: Triazine-based covalent organic framework material and oleic acid were dispersed separately in anhydrous ethanol and ultrasonically treated for 10-35 min to form a triazine-based covalent organic framework material dispersion and an oleic acid dispersion. The triazine-based covalent organic framework material dispersion and the oleic acid dispersion were mixed and ultrasonically treated at 30℃ to obtain a modified triazine-based covalent organic framework material mixture. The solid was separated by centrifugation and washed at least 3 times with anhydrous ethanol. The solid was then dried in a vacuum drying oven at 110℃ for 14 hours under a vacuum of 0.01 Pa. Oleic acid-modified triazine-based covalent organic framework material was obtained.

[0059] The weight ratio of oleic acid to triazine covalent organic framework material is 1.5:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:10mL, and the weight-to-volume ratio of the triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:20mL.

[0060] (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The surfactant is coconut oil diethanolamide, the rust-transfer agent is 5% hydrochloric acid by weight, and the rust-transfer stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.3. The composition includes 20 parts by weight of water, 25 parts by weight of waterborne epoxy resin, 10 parts by weight of surfactant, 0.3 parts by weight of rust-transfer agent, and 0.2 parts by weight of rust-transfer stabilizer.

[0061] (4) Add filler, curing agent, pigment, thickener, defoamer, dispersant and anti-settling agent to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0062] The mixture contains 5 parts by weight of filler, 10 parts by weight of curing agent, 1 part by weight of pigment, 0.5 parts by weight of defoamer, 1 part by weight of thickener, 1 part by weight of dispersant and 1 part by weight of anti-settling agent.

[0063] The filler is graphene with a particle size of 50nm, the curing agent is m-phenylenediamine, the pigment is titanium dioxide, the thickener is polyacrylate, the defoamer is BYK011, the dispersant is BYK190, and the anti-settling agent is BYK-410.

[0064] Example 2: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 1 is that: (1) Preparation of triazine-based covalent organic framework materials: At room temperature, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was then ultrasonically dispersed to form a mixed solution. The reaction vessel was then placed in an oil bath at 120°C and reacted for 14 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1.2:21:31:26; (2) Preparation of oleic acid-modified triazine-based covalent organic framework material: Triazine-based covalent organic framework material and oleic acid were dispersed separately in anhydrous ethanol and ultrasonically treated for 12 min to form a triazine-based covalent organic framework material dispersion and an oleic acid dispersion. The triazine-based covalent organic framework material dispersion and the oleic acid dispersion were mixed and ultrasonically treated at 34℃ to obtain a modified triazine-based covalent organic framework material mixture. The solid was separated by centrifugation and washed at least 3 times with anhydrous ethanol. It was then dried in a vacuum drying oven at 125℃ for 13 hours under a vacuum of 1.5 Pa. Oleic acid-modified triazine-based covalent organic framework material was obtained.

[0065] The weight ratio of oleic acid to triazine covalent organic framework material is 1.8:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:12mL, and the weight-to-volume ratio of the triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:28mL.

[0066] (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust-converting stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.4. The rust-converting agent is a mixture of hydrochloric acid and phytic acid at a weight ratio of 1:2, with a mass percentage of 8%. The mixture contains 30 parts by weight of water, 30 parts by weight of waterborne epoxy resin, 11 parts by weight of surfactant, 0.4 parts by weight of rust-converting agent, and 0.3 parts by weight of rust-converting stabilizer.

[0067] (4) Add filler, curing agent, pigment, thickener, defoamer, dispersant and anti-settling agent to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0068] The composition includes 7 parts by weight of filler, 11.5 parts by weight of curing agent, 2 parts by weight of pigment, 0.6 parts by weight of defoamer, 1.5 parts by weight of thickener, 2 parts by weight of dispersant and 1.5 parts by weight of anti-settling agent.

[0069] The filler is graphene and mica in a weight ratio of 2:1.

[0070] Example 3: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 1 is that: (1) Preparation of triazine-based covalent organic framework materials: At room temperature, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was then placed in an oil bath at 130°C and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1.3:23:33:27; (2) Preparation of oleic acid-modified triazine-based covalent organic framework material: Triazine-based covalent organic framework material and oleic acid were dispersed separately in anhydrous ethanol and ultrasonically treated for 10-35 min to form a triazine-based covalent organic framework material dispersion and an oleic acid dispersion. The triazine-based covalent organic framework material dispersion and the oleic acid dispersion were mixed and ultrasonically treated at 38℃ to obtain a modified triazine-based covalent organic framework material mixture. The solid was separated by centrifugation and washed at least 3 times with anhydrous ethanol. It was then dried in a vacuum drying oven at 130℃ for 10 hours under a vacuum of 2 Pa to obtain the oleic acid-modified triazine-based covalent organic framework material.

[0071] The weight ratio of oleic acid to triazine covalent organic framework material is 2.1:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:14mL, and the weight-to-volume ratio of the triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:36mL.

[0072] (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust-converting stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.5. The rust-converting agent is a mixture of 10% hydrochloric acid and phytic acid in a weight ratio of 1:3, wherein the mixture contains 45 parts by weight of water, 35 parts by weight of waterborne epoxy resin, 12 parts by weight of surfactant, 0.5 parts by weight of rust-converting agent, and 0.4 parts by weight of rust-converting stabilizer.

[0073] (4) Add filler, curing agent, pigment, thickener, defoamer, dispersant and anti-settling agent to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0074] The composition includes 9.5 parts by weight of filler, 13 parts by weight of curing agent, 3.5 parts by weight of pigment, 0.7 parts by weight of defoamer, 2 parts by weight of thickener, 3 parts by weight of dispersant, and 2 parts by weight of anti-settling agent. The filler is a mixture of molybdenum disulfide and boron nitride in a weight ratio of 2:1.

[0075] Example 4: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 3 is that: (1) Preparation of triazine-based covalent organic framework materials: At room temperature, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was then placed in an oil bath at 140°C and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1.5:25:40:28; (2) Preparation of oleic acid-modified triazine-based covalent organic framework material: Triazine-based covalent organic framework material and oleic acid were dispersed separately in anhydrous ethanol and ultrasonically treated for 10-35 min to form a triazine-based covalent organic framework material dispersion and an oleic acid dispersion. The triazine-based covalent organic framework material dispersion and the oleic acid dispersion were mixed and ultrasonically treated at 45℃ to obtain a modified triazine-based covalent organic framework material mixture. The solid was separated by centrifugation and washed at least 3 times with anhydrous ethanol. It was then dried in a vacuum drying oven at 140℃ for 10 hours under a vacuum of 5 Pa to obtain the oleic acid-modified triazine-based covalent organic framework material.

[0076] The weight ratio of oleic acid to triazine covalent organic framework material is 3:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:20mL, and the weight-to-volume ratio of the triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:45mL.

[0077] (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust-converting stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.7. The rust-converting agent is a mixture of 5% hydrochloric acid and salicylic acid in a weight ratio of 1:2, wherein the mixture contains 60 parts by weight of water, 40 parts by weight of waterborne epoxy resin, 12 parts by weight of surfactant, 0.6 parts by weight of rust-converting agent, and 0.4 parts by weight of rust-converting stabilizer.

[0078] (4) Add filler, curing agent, pigment, thickener, defoamer, dispersant and anti-settling agent to dispersion according to the weight to obtain rust-to-rust anti-corrosion coating.

[0079] The composition includes 12 parts by weight of filler, 15 parts by weight of curing agent, 5 parts by weight of pigment, 0.7 parts by weight of defoamer, 1-2.5 parts by weight of thickener, 3 parts by weight of dispersant and 2 parts by weight of anti-settling agent.

[0080] Example 5: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 3 is that: (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust stabilizer consists of zinc phosphate, oleic acid-modified triazine covalent organic framework material, and 1,4-diaminoanthraquinone in a weight ratio of 1:0.3:0.03.

[0081] Example 6: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 3 is that: (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust stabilizer consists of zinc phosphate, oleic acid-modified triazine covalent organic framework material, and 1,4-diaminoanthraquinone in a weight ratio of 1:0.5:0.05.

[0082] Example 7: A rust-reducing anti-corrosion coating and its preparation method, the preparation method comprising the following steps: The difference from Example 3 is that: (3) Add waterborne epoxy resin, surfactant, rust-removing agent, rust-removing stabilizer and water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; The rust stabilizer consists of zinc phosphate, oleic acid-modified triazine covalent organic framework material, and 1,4-diaminoanthraquinone in a weight ratio of 1:0.7:0.08.

[0083] Comparative Example 1 The difference from Example 3 is that: (3) The rust stabilizer is a triazine covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.2.

[0084] Comparative Example 2 The difference from Example 3 is that: (3) The rust stabilizer is a triazine covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.8.

[0085] Comparative Example 3 The difference from Example 3 is that: (3) The rust stabilizer is zinc phosphate.

[0086] Comparative Example 4 The difference from Example 3 is that: (3) The rust stabilizer is an oleic acid-modified triazine-based covalent organic framework material.

[0087] Comparative Example 5 The difference from Example 3 is that: (3) The rust stabilizer is 1,4-diaminoanthraquinone.

[0088] Comparative Example 6 The difference from Example 3 is that: The preparation of the modified triazine covalent organic framework material in step (2) is not carried out, and the rust stabilizer is the triazine covalent organic framework material.

[0089] Comparative Example 7 The difference from Example 3 is that: (3) No rust-converting stabilizer is added to the rust-converting anti-corrosion coating.

[0090] Experimental Example The anti-corrosion coatings prepared in Examples 1 to 7 and Comparative Examples 1 to 7 were applied to the surface of steel structures by brushing to form a coating with a dry film thickness of 50-55 μm. The hardness, water resistance, impact resistance, and adhesion of the coatings were tested. The salt spray resistance of the coatings was also tested. Each experiment was performed in at least three parallel tests, and the average value was taken. The results are shown in Table 1.

[0091] The testing standards in the experimental examples are as follows: Pencil method for determining the hardness of paint and varnish films (GB / T 6739-2022) Test method for water resistance of paint film (GB / T 1733-1993) Test method for impact resistance of paint film (GB / T 1732-2020) Determination of resistance to neutral salt spray in paints and varnishes (GB / T 1771-2007) Table 1

[0092] As shown in Table 1, the anti-corrosion coatings prepared in Examples 1 to 7 exhibit significantly improved performance compared to those prepared in Comparative Examples 1 to 7. Among them, the coatings in Examples 3 to 7 show the highest hardness. Compared to Comparative Example 1, the hardness and salt spray resistance of the coatings in Examples 3 to 7 are significantly improved. Since the rust-removing stabilizer in Comparative Example 1 did not use an oleic acid-modified triazine-based covalent organic framework material, it indicates that the protective film formed on the steel structure surface by the rust-removing agent alone has poorer density than the coating with the oleic acid-modified triazine-based covalent organic framework material. This suggests that the oleic acid-modified triazine-based covalent organic framework material can react with the steel structure substrate surface to form a metal complex, improving the bonding with the steel structure surface. Simultaneously, it works synergistically with the rust-removing agent to promote the stability of the bonding between the rust-removing agent and the steel structure surface.

[0093] The water resistance test showed that the anti-corrosion coatings prepared in Examples 1 to 7 had much better water resistance than those in Comparative Examples 1 to 7. Comparing Comparative Examples 4 and 6 further demonstrated that the excellent water resistance of the coatings in this application is not only due to the presence of C=C, C=O, NH, and -CH groups in the oleic acid-modified triazine-based covalent organic framework material, which can react with metals, allowing the oleic acid-modified triazine-based covalent organic framework material to react with the steel structure substrate surface to form a metal complex, but also because oleic acid is grafted onto the triazine-based covalent organic framework material... Regarding the organic framework material, on the one hand, the presence of oleic acid carboxyl groups can promote the bonding stability between the rust stabilizer and the steel structure surface. On the other hand, oleic acid contains long-chain alkanes, and the presence of long-chain alkanes is hydrophobic, which is beneficial for the anti-corrosion coating to have a good shielding effect against external water and water vapor after the coating is applied. This greatly reduces the chemical and / or electrochemical corrosion caused by water wetting of the anti-corrosion coating. While improving the stable bonding between the steel structure surface and the anti-corrosion coating, it also shields against the erosion of external corrosive media. Under the dual effect, the anti-corrosion performance of the anti-corrosion coating is significantly improved.

[0094] Observing the impact resistance also demonstrates that the rust-reversing stabilizer reacts with the steel structure substrate surface and works synergistically with the rust-reversing agent to improve the adhesion between the anti-corrosion coating and the steel structure surface. Simultaneously, it renders the steel structure surface inactive, making it difficult to react with other substances, such as oxygen and water in the air. Furthermore, the rust-reversing stabilizer, composed of zinc phosphate, oleic acid-modified triazine-based covalent organic framework material, and 1,4-diaminoanthraquinone, significantly improves the adhesion between the anti-corrosion coating and the steel structure surface, enhances the stability of the protective film on the steel structure surface, and thus improves the anti-corrosion effect of the coating on the steel structure surface.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A rust-reversing anti-corrosion coating, characterized in that, The rust-reversing anti-corrosion coating consists of the following components by weight: Water: 20-60 parts by weight; Waterborne epoxy resin: 25-40 parts by weight; Surfactant: 10-12 parts by weight; Filler: 5-12 parts by weight; Rust remover: 0.3-0.6 parts by weight; Hardener: 10-15 parts by weight; Pigment: 1-5 parts by weight; Rust stabilizer: 0.2-0.4 parts by weight; Defoamer: 0.5-0.7 parts by weight; Thickener: 1-2.5 parts by weight; The rust-reversing stabilizer is a triazine-based covalent organic framework material modified with zinc phosphate and oleic acid in a weight ratio of 1:0.3-0.

7. The preparation method of the oleic acid-modified triazine-based covalent organic framework material includes the following steps: (1) Preparation of triazine-based covalent organic framework materials: 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was placed in an oil bath at 110-140℃ and reacted for 12-24 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, mesitylene, 1,4-dioxane and acetic acid is 1:1-1.5:20-25:35-40:25-28; (2) Preparation of oleic acid modified triazine covalent organic framework material: Triazine covalent organic framework material and oleic acid are dispersed in anhydrous ethanol and ultrasonically treated for 10-35 min to form triazine covalent organic framework material dispersion and oleic acid dispersion. The triazine covalent organic framework material dispersion and oleic acid dispersion are mixed and ultrasonically treated at a temperature of 30-45℃ to obtain modified triazine covalent organic framework material mixture. The solid is separated by centrifugation and washed with anhydrous ethanol at least 3 times to obtain oleic acid modified triazine covalent organic framework material. The weight ratio of oleic acid to triazine covalent organic framework material is 1.5-3:1, the weight-to-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:10-20mL, and the weight-to-volume ratio of triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:20-45mL.

2. The anti-corrosion coating for rust-to-rust conversion according to claim 1, characterized in that, The surfactant is coconut oil diethanolamide or dodecyl dimethyl betaine.

3. The anti-corrosion coating for rust-to-rust conversion according to claim 1, characterized in that, The filler is one or more of graphene, molybdenum disulfide, mica, and boron nitride.

4. The anti-corrosion coating for rust-to-rust conversion according to claim 3, characterized in that, The graphene, molybdenum disulfide, mica, and boron nitride have a particle size of 10-100 nm.

5. The anti-corrosion coating for rust-to-rust conversion according to any one of claims 1-4, characterized in that, The rust-removing agent is one or more of hydrochloric acid, phytic acid, salicylic acid, tannic acid, ascorbic acid, and oxalic acid.

6. The anti-corrosion coating for rust-to-rust conversion according to claim 1, characterized in that, The pigment is one of titanium dioxide, zinc barium white, zinc oxide, antimony oxide, iron oxide red, hydrated iron yellow, and iron black.

7. The anti-corrosion coating for rust-to-rust conversion according to claim 1, characterized in that, The defoamer is one or more of BYK011, BYK012, and BYK024.

8. The anti-corrosion coating for rust-to-rust conversion according to claim 1, characterized in that, The thickener is any one of polyacrylate, hydroxymethyl cellulose, and agar.

9. A method for preparing a rust-to-rust anti-corrosion coating, used to prepare the rust-to-rust anti-corrosion coating according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: (1) Preparation of triazine-based covalent organic framework materials: 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1,3,5-tris(4-formylphenyl)benzene, and mesitylene were added sequentially to a reaction vessel, followed by the addition of 1,4-dioxane and acetic acid. The mixture was ultrasonically dispersed to form a mixed solution. The reaction vessel was placed in an oil bath at 110-140℃ and reacted for 12-24 hours. After the reaction was completed, the mixture was cooled to room temperature to obtain a preliminary product of triazine-based covalent organic framework material. The preliminary product of triazine-based covalent organic framework material was washed several times with tetrahydrofuran and acetone to obtain the triazine-based covalent organic framework material. The molar ratio of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine to 1,3,5-tris(4-formylphenyl)benzene, the mesitylene, the 1,4-dioxane and the acetic acid is 1:1-1.5:20-25:35-40:25-28; (2) Preparation of oleic acid modified triazine covalent organic framework material: The triazine covalent organic framework material and oleic acid are dispersed in anhydrous ethanol and ultrasonically treated for 10-35 min to form a triazine covalent organic framework material dispersion and an oleic acid dispersion. The triazine covalent organic framework material dispersion and the oleic acid dispersion are mixed and ultrasonically treated at a temperature of 30-45℃ to obtain a modified triazine covalent organic framework material mixture. The solid is separated by centrifugation and washed with anhydrous ethanol at least 3 times to obtain the oleic acid modified triazine covalent organic framework material. (3) Add the waterborne epoxy resin, the surfactant, the rust-removing agent, the rust-removing stabilizer and the water to a container according to the weight parts, and stir and mix at room temperature to form a dispersion; (4) The filler, the curing agent, the pigment, the thickener and the defoamer are added to the dispersion in parts by weight to obtain the rust-to-rust anti-corrosion coating.

10. The method for preparing the rust-converting anti-corrosion coating according to claim 9, characterized in that, The preparation steps of the oleic acid modified triazine covalent organic framework material further include: the weight ratio of oleic acid to the triazine covalent organic framework material is 1.5-3:1, the weight-volume ratio of oleic acid to anhydrous ethanol in the oleic acid dispersion is 1g:10-20mL, and the weight-volume ratio of the triazine covalent organic framework material to anhydrous ethanol in the triazine covalent organic framework material dispersion is 1g:20-45mL.

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