Epoxy anti-corrosion coating capable of being painted with rust and preparation method thereof

Abstract

The present invention relates to the field of anticorrosive coatings, specifically a kind of epoxy anticorrosive coating that can be coated with rust and preparation method thereof, solve coating and rust infiltration and bonding process, solid nanoparticles are difficult to disperse into rust, cause paint film impact resistance weak, be difficult to the problem of long-term corrosion resistance, technical scheme includes epoxy component A and curing component B, wherein epoxy component A is by weight by 30 50 parts of epoxy resin, 10 15 parts of modified nano filler, 1 2 parts of migration enhancer, 6 8 parts of diluent and 8 12 parts of fumaric acid composition;Wherein curing component B is by weight by 20 30 parts of ethyl acetate, 3 8 parts of rust converter, 2 5 parts of surfactant and 5 10 parts of penetrant composition.The present invention can realize the migration ability of nano solid particles between rust layers, increases the degree of combination and quantity of the two, thus forming more uniformly strong hard particles, enhances the impact resistance and corrosion resistance of coating.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-corrosion coatings, and in particular to an epoxy anti-corrosion coating capable of being coated with rust and a preparation method thereof. Background Art

[0002] Rust-resistant coatings are a type of corrosion-inhibiting coating that can be applied directly to rusted steel surfaces. When applied to metal surfaces with residual rust, they stabilize, passivate, or convert the rust, turning the active rust into harmless substances, achieving both rust prevention and protection. Rust-resistant coatings are categorized into conversion-type, stabilization-type, and penetrating-type coatings based on the type of raw material.

[0003] First, there are conversion-type rust-removing coatings. These use inorganic acids or phosphoric acid to convert rust into harmless, insoluble complexes and chelates. These complexes and chelates are fixed to the steel surface through the adhesion of film-forming substances. However, the amount of conversion solution used is difficult to control for steel surfaces with uneven rust layers. A small amount can lead to incomplete conversion, while a large amount can corrode the metal and release hydrogen, affecting the coating's adhesion to the metal. Their adhesion is generally lower than that of stabilizing and penetrating coatings. Second, there are stable rust-removing coatings. These rely on zinc chromate, zinc phosphate, and other agents to form insoluble complexes and stable iron oxides on the rust, passivating the metal and achieving stabilization. However, since they do not contain organic and inorganic acids or other conversion agents, their effect on rust is minimal, and their stabilization is slow. It is impossible to convert all rust into stable iron oxide using anti-rust pigments and corrosion inhibitors. Furthermore, conditions for further rust formation exist, and the applied rust layer cannot be too thick. The third type is penetrating rust-resistant paint, which is a low-viscosity, high-solids paint with a solid content of >52% and strong permeability. It uses the wetting and penetrating effect of the paint on loose rust to divide the rust and surround it in the paint, making it inactive and preventing further development of rust. At the same time, it also uses the effect of special pigments to passivate or transform harmful iron compounds in the rust layer into stable and harmless substances. However, the disadvantage is that it must have sufficient penetrating ability to penetrate the entire loose rust layer and make the rust layer bonded to form a continuous closed coating. The rust-resistant paint must also be sufficiently reactive to the rust layer, otherwise the effect will be poor.

[0004] Therefore, the existing technology mostly uses phytic acid or tannic acid or substances with phenolic hydroxyl groups to cross-link with resin to penetrate and coat the rust, thereby forming isolation and corrosion protection. However, the impact resistance of epoxy resin is poor. After combining with loose rust, moisture and oxygen are present in the formed paint film, and the impact resistance of the paint film becomes poor, which is easily damaged by side scratches. Therefore, when solid particles are used to increase its wear resistance, it is found that nano solid particles are difficult to migrate into the interior of the rust, and it is difficult to achieve good extension after modification. They cannot be well combined with the rust to form a relatively strong complex. Summary of the Invention

[0005] In order to solve the problem that during the penetration and bonding process of epoxy resin type paint and rust, solid nanoparticles are difficult to disperse into the rust to form a uniform hard structure, resulting in weak impact resistance of the paint film and difficulty in long-term corrosion protection.

[0006] The present invention provides an epoxy anti-corrosion coating capable of being coated with rust and a preparation method thereof. The technical solution of the epoxy anti-corrosion coating is as follows:

[0007] A rust-resistant epoxy anti-corrosion coating comprises an epoxy component A and a curing component B, wherein the epoxy component A comprises, by weight, 30-50 parts of an epoxy resin, 10-15 parts of a modified nanofiller, 1-2 parts of a migration enhancer, 6-8 parts of a diluent, and 8-12 parts of fumaric acid; and the curing component B comprises, by weight, 20-30 parts of ethyl acetate, 3-8 parts of a rust converter, 2-5 parts of a surfactant, and 5-10 parts of a penetrant.

[0008] The preparation method of the modified nanofiller is as follows:

[0009] A1. Dissolve carboxymethyl cellulose and gallic acid in water to obtain a cross-linking solution;

[0010] A2. placing the nanoparticles in water and adjusting the pH with an alkali solution to obtain a first dispersion of the nanoparticles;

[0011] A3, mixing diethylene glycol phthalate diacrylate with water to obtain a modified treatment solution;

[0012] A4. Dropwise adding the modified treatment liquid to the first dispersion of nanoparticles, centrifuging to obtain modified silica, then dispersing the modified nanoparticles in water to form a second dispersion of silica, dropwise adding the crosslinking liquid to the second dispersion of silica, and centrifuging to obtain a modified nanofiller;

[0013] The migration enhancer is humic acid.

[0014] The present application adds nanoparticles to the coating, utilizes the mutual combination of nanoparticles and rust, and forms a mutually supporting structure with the cross-linked resin skeleton. The higher surface energy of the nanoparticles is utilized to make the rust react with functional groups during the penetration process, thereby reducing the surface energy of the nanoparticles, thereby promoting the aggregation between the nanoparticles and rust molecules, achieving agglomeration, and then reducing the loose structure to form a harder and more compact solid form, thereby having higher impact resistance, increasing corrosion resistance, and protecting the underlying metal.

[0015] The present application also utilizes humic acid as a migration enhancer. In the examples, it is found that the addition of humic acid can promote the migration ability of nanoparticles combined with diethylene glycol diacrylate phthalate, thereby allowing negatively charged solid nanoparticles that are difficult to enter the rust interlayer to enter the rust layer and disperse more evenly. The nanoparticles are more and more tightly combined with the underlying rust. The role of diethylene glycol diacrylate phthalate is to produce ionization effect to generate quaternary ammonium cations, which rely on the interaction of charges to adsorb on the surface of nanoparticles, thereby improving the compatibility of nanoparticles and thus compounding with carboxymethyl cellulose. The role of humic acid is to reduce the interaction between nanoparticles and negatively charged rust through electrostatic repulsion and steric hindrance competition, thereby improving the migration ability of nanoparticles, and then improving the degree of combination between rust and nanoparticles, and increasing the impact resistance of the paint film surface.

[0016] Preferably, the diluent in the epoxy component A is butyl glycidyl ether or 1,4-butanediol diglycidyl ether.

[0017] Preferably, the rust conversion agent in the curing component B is tannic acid or phytic acid, the surfactant is sodium dodecylbenzenesulfonate or sodium dioctylsulfosuccinate, and the penetrant is cyclohexanone.

[0018] In this application, nanoparticles aggregate rust molecules to form more aggregated hard particles, and then tannic acid and phytic acid form a tougher surface paint film with these hard particles, which are connected together with a large skeleton to form a second layer of corrosion protection structure. The presence of the penetrant cyclohexanone makes it easier for the nanoparticles to enter the interior of the rust.

[0019] Preferably, the nanoparticles are silicon dioxide or titanium dioxide, and the particle size of the nanoparticles is 10-40 nm.

[0020] Nano-silica increases the degree of aggregation of molecules in rust, and titanium dioxide increases the weather resistance of the material, making it more resistant.

[0021] Preferably, the mass ratio of carboxymethyl cellulose to gallic acid in step A1 and the mass ratio of nanoparticles in step A2 is 4-6:3-4:1-3.

[0022] The gallic acid of the present application can aggregate more iron molecules in a unit space to form a larger complex or chelate, thereby stabilizing a solid substance.

[0023] Preferably, in step A3, the volume ratio of diethylene glycol phthalate diacrylate to water is 4:10-15, and the solid-liquid ratio of the diethylene glycol phthalate diacrylate to the nano-silica is 1-3 g:16 mL.

[0024] The present application found in the examples that a specific combination of diethylene glycol phthalate diacrylate and nano-silica can achieve a better migration effect, and that too much or too little diethylene glycol phthalate diacrylate will reduce the migration ability of nanoparticles.

[0025] Preferably, the modified dispersion and the first silica dispersion in step A4 are further subjected to ultrasonic treatment before centrifugal separation, with the ultrasonic power being 800-1200 W and the ultrasonic time being 20-35 min.

[0026] The present application also provides a method for preparing an epoxy anti-corrosion coating that can be coated with rust. The specific preparation steps of the preparation method are as follows:

[0027] S1. Mixing an epoxy resin and a diluent, then adding a modified nanofiller and homogenizing and dispersing the mixture to obtain a homogenous liquid, and then dropping a migration enhancer and fumaric acid into the homogenous liquid while stirring with a stirring rod to obtain an epoxy component A.

[0028] S2. The rust converter and the surfactant are placed in ethyl acetate and homogeneously mixed, and then the penetrant is added and stirred to obtain a curing component B;

[0029] S3. Mixing the epoxy component A and the curing component B to obtain an epoxy anti-corrosion coating.

[0030] Preferably, the homogenizing and dispersing operations in S1 are magnetic stirring and ultrasonic treatment, the ultrasonic power is 1200 W, the ultrasonic treatment time is 15 min, and the number of ultrasonic treatments is 2 times.

[0031] The rust-coating epoxy anti-corrosion coating prepared in the present application can be applied to metal surfaces with a rust layer thickness of less than 1 mm.

[0032] The beneficial effects of the present invention are as follows:

[0033] The present application modifies the nanoparticles, which can enhance the aggregation and hardness of the rust complex, and enhance the density of the paint film, thereby providing a greater density, higher impact resistance and corrosion resistance.

[0034] By modifying nano-silica with diethylene glycol diacrylate phthalate, the binding ability and aggregation degree of nano-silica to rust are enhanced, and hard particles with a higher density are obtained. The ability to withstand external scratches is improved, the coating is not easily lost, and the corrosion resistance is improved.

[0035] The use of humic acid competes for the electrostatic repulsion and steric hindrance between nanoparticles and rust, thereby facilitating the migration of nanoparticles and increasing the number of deep rust and surface nanoparticles combined, resulting in stronger binding energy and better corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 1 is a trend diagram of the impact resistance of the embodiments of the present invention and the comparative example.

[0037] Figure 2 2 is a comparison chart of the anti-corrosion performance of the embodiment of the present invention and the comparative example. DETAILED DESCRIPTION

[0038] The following will refer to the attached Figures 1 to 2 The embodiments of the present invention are described in detail. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0039] Preparation Example 1

[0040] Preparation of modified nanofillers

[0041] A1. Dissolve 25 g of carboxymethyl cellulose and 18 g of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0042] A2. Place 10 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0043] A3. Mix 80 mL of diethylene glycol phthalate diacrylate with 250 mL of water to obtain a modified treatment solution;

[0044] A4. The modified treatment liquid is added dropwise to the first dispersion of nanoparticles, treated using an ultrasonic processor with a power of 1000 W for 30 minutes, and centrifuged to obtain modified silica. The modified nanoparticles are then dispersed in water to form a second dispersion of silica. The cross-linking liquid is added dropwise to the second dispersion of silica, and centrifuged to obtain a modified nanofiller.

[0045] Preparation Example 2

[0046] Preparation of modified nanofillers

[0047] A1. Dissolve 20 g of carboxymethyl cellulose and 15 gg of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0048] A2. Place 5 g of titanium dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0049] A3. Mix 80 mL of diethylene glycol phthalate diacrylate with 200 mL of water to obtain a modified treatment solution;

[0050] A4. The modified treatment liquid is added dropwise to the first dispersion of nanoparticles, treated with an 800W ultrasonic processor for 20 minutes, and centrifuged to obtain modified silica. The modified nanoparticles are then dispersed in water to form a second dispersion of silica. The cross-linking liquid is added dropwise to the second dispersion of silica, and centrifuged to obtain a modified nanofiller.

[0051] Preparation Example 3

[0052] Preparation of modified nanofillers

[0053] A1. Dissolve 30 g of carboxymethyl cellulose and 20 g of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0054] A2. Place 15 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0055] A3. Mix 80 mL of diethylene glycol phthalate diacrylate with 300 mL of water to obtain a modified treatment solution;

[0056] A4. The modified treatment liquid was added dropwise to the first dispersion of nanoparticles, and the mixture was treated using an ultrasonic processor with a power of 1200 W for 35 minutes. The modified silica was obtained by centrifugation. The modified nanoparticles were then dispersed in water to form a second dispersion of silica. The cross-linking liquid was added dropwise to the second dispersion of silica, and the mixture was centrifuged to obtain a modified nanofiller.

[0057] Preparation Example 4—Nanoparticles not treated with diethylene glycol phthalate diacrylate

[0058] Preparation of modified nanofillers

[0059] A1. Dissolve 25 g of carboxymethyl cellulose and 18 g of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0060] A2. Place 10 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0061] A3. Add the first dispersion of nanoparticles dropwise into the cross-linking solution, and centrifuge to obtain a modified nanofiller.

[0062] Preparation Example 5 - Excessive use of diethylene glycol phthalate diacrylate to react with nanoparticles

[0063] Preparation of modified nanofillers

[0064] A1. Dissolve 25 g of carboxymethyl cellulose and 18 g of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0065] A2. Place 10 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0066] A3. Mix 250 mL of diethylene glycol phthalate diacrylate with 250 mL of water to obtain a modified treatment solution;

[0067] A4. The modified treatment liquid is added dropwise to the first dispersion of nanoparticles, treated using an ultrasonic processor with a power of 1000 W for 30 minutes, and centrifuged to obtain modified silica. The modified nanoparticles are then dispersed in water to form a second dispersion of silica. The cross-linking liquid is added dropwise to the second dispersion of silica, and centrifuged to obtain a modified nanofiller.

[0068] Preparation Example 6 - Using too little diethylene glycol phthalate diacrylate to react with nanoparticles

[0069] Preparation of modified nanofillers

[0070] A1. Dissolve 25 g of carboxymethyl cellulose and 18 g of gallic acid in 1000 mL of water to obtain a cross-linked solution.

[0071] A2. Place 10 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles;

[0072] A3. Mix 25 mL of diethylene glycol phthalate diacrylate with 250 mL of water to obtain a modified treatment solution;

[0073] A4. The modified treatment liquid is added dropwise to the first dispersion of nanoparticles, treated using an ultrasonic processor with a power of 1000 W for 30 minutes, and centrifuged to obtain modified silica. The modified nanoparticles are then dispersed in water to form a second dispersion of silica. The cross-linking liquid is added dropwise to the second dispersion of silica, and centrifuged to obtain a modified nanofiller.

[0074] Preparation Example 7—Nanoparticles not treated with crosslinking solution

[0075] Preparation of modified nanofillers

[0076] A1. Place 10 g of silicon dioxide with a particle size of 10-40 nm in 1200 mL of water and adjust the pH to 10 with sodium hydroxide solution to obtain a first dispersion of nanoparticles.

[0077] A2. Mix 80 mL of diethylene glycol phthalate diacrylate with 250 mL of water to obtain a modified treatment solution;

[0078] A3. The modified treatment liquid was added dropwise to the first dispersion of nanoparticles, and treated with an ultrasonic processor with a power of 1000 W for 30 minutes. The modified silica was obtained by centrifugation. The modified nanoparticles were then dispersed in water to form a second dispersion of silica, which was then centrifuged to obtain a nanofiller.

[0079] Example 1

[0080] An epoxy anti-corrosion coating capable of being painted with rust

[0081] S1. 40 parts of epoxy resin and 7 parts of butyl glycidyl ether were mixed by weight, and then 13 parts of the modified nanofiller in Preparation Example 1 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 1.5 parts of humic acid and 10 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain an epoxy component A.

[0082] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0083] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0084] Example 2

[0085] An epoxy anti-corrosion coating capable of being painted with rust

[0086] S1. Mix 30 parts of epoxy resin and 6 parts of 1,4-butanediol diglycidyl ether by weight, then add 10 parts of the modified nanofiller in Preparation Example 2, and perform two ultrasonic treatments after magnetic stirring. The ultrasonic power is 1200 W, and the ultrasonic treatment time is 15 minutes each time to obtain a homogeneous liquid. Then, 1 part of humic acid and 8 parts of fumaric acid are added dropwise to the homogeneous liquid, and a stirring rod is used to stir during the addition to obtain epoxy component A;

[0087] S2. 3 parts of tannic acid and 2 parts of dioctyl sodium sulfosuccinate were placed in 20 parts of ethyl acetate and homogeneously mixed, and then 5 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0088] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0089] Example 3

[0090] An epoxy anti-corrosion coating capable of being painted with rust

[0091] S1. 50 parts of epoxy resin and 8 parts of butyl glycidyl ether were mixed by weight, and then 15 parts of the modified nanofiller in Preparation Example 3 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 2 parts of humic acid and 12 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain an epoxy component A.

[0092] S2. 8 parts of phytic acid and 5 parts of dioctyl sodium sulfosuccinate were placed in 30 parts of ethyl acetate and homogeneously mixed, and then 10 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0093] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0094] Comparative Example 1

[0095] An epoxy anti-corrosion coating capable of being painted with rust

[0096] S1. 40 parts of epoxy resin and 7 parts of butyl glycidyl ether were mixed by weight, and then 12 parts of the modified nanofiller in Preparation Example 4 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 1.5 parts of humic acid and 10 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain an epoxy component A.

[0097] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0098] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0099] Comparative Example 2

[0100] An epoxy anti-corrosion coating capable of being painted with rust

[0101] S1. 40 parts of epoxy resin and 7 parts of butyl glycidyl ether were mixed by weight, and then 12 parts of the modified nanofiller in Preparation Example 5 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 1.5 parts of humic acid and 10 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain epoxy component A.

[0102] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0103] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0104] Comparative Example 3

[0105] An epoxy anti-corrosion coating capable of being painted with rust

[0106] S1. 40 parts of epoxy resin and 7 parts of butyl glycidyl ether were mixed by weight, and then 12 parts of the modified nanofiller in Preparation Example 6 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 1.5 parts of humic acid and 10 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain an epoxy component A.

[0107] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0108] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0109] Comparative Example 4

[0110] An epoxy anti-corrosion coating capable of being painted with rust

[0111] S1. 40 parts of epoxy resin and 7 parts of butyl glycidyl ether were mixed by weight, and then 12 parts of the modified nanofiller in Preparation Example 7 were added. After magnetic stirring, the mixture was ultrasonically treated twice at an ultrasonic power of 1200 W and a ultrasonic treatment time of 15 min each time to obtain a homogeneous solution. 1.5 parts of humic acid and 10 parts of fumaric acid were added dropwise to the homogeneous solution, and a stirring rod was used to stir the mixture during the addition to obtain an epoxy component A.

[0112] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0113] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0114] Comparative Example 5 - No humic acid added

[0115] An epoxy anti-corrosion coating capable of being painted with rust

[0116] S1. Mix 40 parts of epoxy resin and 7 parts of butyl glycidyl ether by weight, then add 12 parts of the modified nanofiller in Preparation Example 1, and perform two ultrasonic treatments after magnetic stirring. The ultrasonic power is 1200 W, and the ultrasonic treatment time is 15 minutes each time to obtain a homogeneous liquid. Then, 10 parts of fumaric acid are added dropwise to the homogeneous liquid while stirring with a stirring rod during the addition to obtain epoxy component A;

[0117] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0118] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0119] Comparative Example 6—No Nanoparticles Used

[0120] An epoxy anti-corrosion coating capable of being painted with rust

[0121] S1. Mix 40 parts of epoxy resin and 7 parts of butyl glycidyl ether by weight, and then dropwise add 1.5 parts of humic acid and 10 parts of fumaric acid to the homogenized liquid while stirring with a stirring rod to obtain epoxy component A;

[0122] S2. 5 parts of phytic acid and 4 parts of sodium dodecylbenzenesulfonate were placed in 25 parts of ethyl acetate and homogeneously mixed, and then 8 parts of cyclohexanone were added and stirred to obtain a curing component B;

[0123] S3. Mixing the epoxy component A prepared in the above steps with the curing component B to obtain an epoxy anti-corrosion coating.

[0124] Experiments and data

[0125] The epoxy anti-corrosion coatings prepared in the above examples and comparative examples were tested for their anti-corrosion performance and impact resistance in the following manner:

[0126] Impact resistance test: The paint film surface is subjected to impact force test according to the test method specified in ISO 6272-2:2002. The unit is cm. The paint film does not fall off or crack under the impact height.

[0127] Anti-corrosion test: The anti-corrosion performance of the paint film was tested according to the test standard specified in JG / T 224-2007. After 1000 hours of salt spray test, there was no blistering or falling off.

[0128] The anti-corrosion performance of the paint film is tested after rubbing the surface.

[0129] The test results are shown in Table 1 below:

[0130] Table 1

[0131]

[0132] The impact resistance of the above embodiment and the comparative example is plotted as follows: Figure 1 As shown; the anti-corrosion performance is compared by drawing a bar chart, such as Figure 2 shown.

[0133] analyze

[0134] According to the data in Table 1 of Examples 1 to 3, the rust-resistant epoxy anti-corrosion coating prepared in the present application has strong impact resistance, can effectively prevent the paint film from falling off, has excellent anti-corrosion performance, and has strong strength.

[0135] According to the experimental data of Comparative Example 1 in Table 1, the epoxy anti-corrosion coating prepared in Comparative Example 1 has poor impact resistance, and its salt spray corrosion resistance decreases after friction. Comparative Example 1 does not use diethylene glycol phthalate diacrylate to treat the nanoparticles. It can be seen that diethylene glycol phthalate diacrylate can change the surface energy of the nanoparticles, increase its connection reaction with carboxymethyl cellulose, and enhance the migration ability of the nanoparticles.

[0136] According to the experimental data of Comparative Examples 2 and 3, the impact resistance of Comparative Examples 2 and 3 decreased significantly, and the corrosion resistance decreased after friction, while Comparative Example 3 decreased the most, and Comparative Example 2 decreased slightly. It can be seen that an appropriate amount of diethylene glycol phthalate diacrylate can effectively enhance the ability of nanoparticles to migrate inside the rust, and then combine with more rust molecules to form denser hard particles, thereby enhancing the corrosion resistance.

[0137] According to the experimental data of Comparative Example 4, the impact resistance of Comparative Example 4 is poor and the initial corrosion resistance is very low, which proves that the connection between carboxymethyl cellulose and gallic acid in the cross-linking liquid can effectively enhance the ability of nanoparticles to aggregate substances and form a denser corrosion protection layer.

[0138] According to the experimental data of Comparative Example 5, the impact resistance of Comparative Example 5 is poor, and its corrosion resistance also decreases to a certain extent after friction. It can be seen that humic acid occupies electrostatic repulsion and steric hindrance, which can effectively increase the migration performance of nanoparticles, so that the nanoparticles can be more deeply connected to the innermost layer of rust for complexation and cross-linking, thereby enhancing its adhesion and further enhancing the corrosion resistance.

[0139] According to the experimental data of Comparative Example 6, Comparative Example 6 does not use nanoparticles, and its impact resistance is the worst. It is most likely to fall off when there is a thick rust layer, and its corrosion resistance is also the lowest. It can be seen that the presence of nanoparticles has the greatest impact on the impact resistance, mainly affecting the presence of the paint film, thereby affecting the adhesion performance of the paint film, thereby improving the corrosion resistance of the paint film.

[0140] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. An epoxy anti-corrosion coating for rust coating, characterized in that: The invention comprises an epoxy component A and a curing component B, wherein the epoxy component A is composed of 30-50 parts by weight of epoxy resin, 10-15 parts by weight of modified nanofiller, 1-2 parts by weight of migration enhancer, 6-8 parts by weight of diluent and 8-12 parts by weight of fumaric acid; wherein the curing component B is composed of 20-30 parts of ethyl acetate, 3-8 parts of rust converter, 2-5 parts of surfactant and 5-10 parts of penetrant by weight; The preparation method of the modified nanofiller is as follows: A1. Dissolve carboxymethyl cellulose and gallic acid in water to obtain a cross-linking solution; A2. placing the silica nanoparticles in water and adjusting the pH with an alkaline solution to obtain a first dispersion of the silica nanoparticles; A3, mixing diethylene glycol phthalate diacrylate with water to obtain a modified treatment solution; A4. Dropwise adding the modified treatment liquid to the first dispersion of silica nanoparticles, centrifuging to obtain modified silica, then dispersing the modified silica in water to form a second dispersion of silica, dropwise adding the crosslinking liquid to the second dispersion of silica, and centrifuging to obtain a modified nanofiller; The migration enhancer is humic acid; The rust conversion agent in the curing component B is tannic acid or phytic acid, the surfactant is sodium dodecylbenzenesulfonate or sodium dioctylsulfosuccinate, and the penetrant is cyclohexanone.

2. The epoxy anti-corrosion coating for rust coating according to claim 1, characterized in that: The diluent in the epoxy component A is butyl glycidyl ether or 1,4-butanediol diglycidyl ether.

3. The epoxy anti-corrosion coating for rust coating according to claim 1, characterized in that: The mass ratio of carboxymethyl cellulose to gallic acid in step A1 and the mass ratio of silicon dioxide nanoparticles in step A2 is 4-6:3-4:1-3.

4. The epoxy anti-corrosion coating for rust coating according to claim 1, characterized in that: In step A3, the volume ratio of diethylene glycol phthalate diacrylate to water is 4:10-15.

5. The method for preparing a rust-coated epoxy anti-corrosion coating according to any one of claims 1 to 4, characterized in that: The specific preparation steps of this preparation method are as follows: S1. Mixing an epoxy resin and a diluent, then adding a modified nanofiller and homogenizing and dispersing the mixture to obtain a homogenous liquid, and then dropwise adding a migration enhancer and fumaric acid to the homogenous liquid while stirring with a stirring rod to obtain an epoxy component A; S2. The rust converter and the surfactant are placed in ethyl acetate and homogeneously mixed, and then the penetrant is added and stirred to obtain a curing component B; S3. Mixing the epoxy component A and the curing component B to obtain an epoxy anti-corrosion coating.

6. The method for preparing a rust-coated epoxy anti-corrosion coating according to claim 5, characterized in that: The homogenous dispersion operation in S1 is magnetic stirring and ultrasonic treatment, the ultrasonic power is 1200 W, the ultrasonic treatment time is 15 min, and the number of ultrasonic treatments is 2.

7. Use of the rust-coated epoxy anti-corrosion paint as described in any one of claims 1 to 4 on a metal surface with a rust layer thickness of less than 1 mm.

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