Two-component anticorrosive paint and preparation method thereof

Abstract

The present application relates to the field of coating technology, and in particular to a two-component anticorrosive paint and a preparation method thereof. A two-component anticorrosive paint comprises component A and component B, wherein the mass ratio of component A to component B is 1:1; component A comprises the following raw materials: 50-55 parts of modified epoxy resin, 35-40 parts of modified pigments and fillers, 2-2.5 parts of dispersants, 0.2-0.4 parts of leveling agents, 0.1-0.3 parts of wetting agents, 0.3-0.5 parts of defoamers, 0.5-0.8 parts of thickeners, and 30-50 parts of solvents; component B comprises the following raw materials: 8-10 parts of curing agents and 10-15 parts of solvents. The two-component anticorrosive paint of the present application has significant advantages in terms of anticorrosion performance, physical properties, and coating effects, and can effectively protect metal surfaces from corrosion and damage in practical applications, and has broad application prospects and economic benefits.

Description

Technical Field

[0001] The present application relates to the field of coating technology, and in particular to a two-component anticorrosive paint and a preparation method thereof. Background Art

[0002] Automotive coatings have strict requirements on appearance, so they have strict requirements on coating quality, spraying environment, and process. However, accidents often occur during the spraying process. For example, due to environmental problems, there are shrinkage holes and particles on the sprayed midcoat. In order to reduce the impact on the coating appearance, the midcoat needs to be polished to remove the defects. However, when spraying the color paint, the polishing marks often cannot be covered, which puts forward new requirements for the color paint.

[0003] As part of the composite coating system of automobiles, automobile paint can not only improve the appearance of the topcoat, but also improve the stone chip resistance and corrosion resistance of the entire coating system, so it is becoming more and more important. Traditional solvent-based automobile paint can hardly meet the requirements of modern automobile decoration and protection. Modern automobile paint must solve the following problems: poor corrosion resistance, slow drying and poor stone chip resistance. Summary of the invention

[0004] The purpose of this application is to provide a two-component anticorrosive paint and a preparation method thereof in view of the shortcomings of the current technology. The two-component anticorrosive paint of this application has the advantages of good water resistance, excellent corrosion resistance, fast drying speed, good stone impact resistance, good impact resistance and high color difference stability.

[0005] In the first aspect, the present application provides a two-component anti-corrosion paint, which adopts the following technical solution:

[0006] A two-component anticorrosive paint comprises a component A and a component B, wherein the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials by mass: 50-55 parts of a modified epoxy resin, 35-40 parts of a modified pigment and filler, 2-2.5 parts of a dispersant, 0.2-0.4 parts of a leveling agent, 0.1-0.3 parts of a wetting agent, 0.3-0.5 parts of a defoamer, 0.5-0.8 parts of a thickener, and 30-50 parts of a solvent; the component B comprises the following raw materials by mass: 8-10 parts of a curing agent and 10-15 parts of a solvent.

[0007] By adopting the above technical scheme, the modified epoxy resin in component A is the main film-forming substance of the two-component anticorrosive paint, which can improve the water resistance and corrosion resistance of the paint film. The modified pigments and fillers in component A cooperate with the modified epoxy resin to improve the wear resistance and impact resistance of the paint film. The dispersant, leveling agent, wetting agent, defoamer, thickener and other additives in component A play a regulating role in the gloss, leveling, surface tension and other properties of the paint film. The curing agent in component B is the curing agent of the two-component anticorrosive paint, which can react with the epoxy resin in component A after the coating film dries to form a strong and wear-resistant paint film. The solvent in component A evaporates after the paint film dries, making the paint film more uniform and firm. The various ingredients between different components work synergistically, so that the two-component anticorrosive paint has excellent overall performance, such as good water resistance, excellent corrosion resistance, fast drying speed, good stone impact resistance, good impact resistance and high color difference stability.

[0008] Preferably, the preparation method of the modified epoxy resin is as follows: 4 parts by mass of methylphenyldimethoxysilane and 10 parts of rosin-based ethylene glycol diglycidyl acrylate are added to a four-mouth reactor equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen conduit, and 0.02 parts of a catalyst tetraisopropyl titanate are added at the same time, and nitrogen is passed through for 15-20 minutes, and then stirring is started. When the temperature is raised to 110-120° C., the mixture is reacted for 4-5 hours under insulation to obtain the modified epoxy resin.

[0009] By adopting the above technical scheme, the prepared modified epoxy resin plays an important role in the two-component anticorrosive paint, improving the water resistance of the paint film: because the modified epoxy resin has a silicon-rich carbon layer structure, it can form a dense paint film surface, improve the waterproof performance of the paint film, and prevent water from corroding the metal substrate. Improve heat resistance, stone impact resistance and impact resistance: the modified epoxy resin can maintain the stability of the paint film at high temperature, enhance the bonding between the resin and the substrate, and improve the wear resistance and impact resistance of the paint film. Compatibility with modified pigments and fillers improves corrosion resistance: the modified epoxy resin improves the corrosion resistance of the paint film through interaction with modified pigments and fillers, so that the pigments and fillers in the paint film can better cover the metal surface, increasing the adhesion and firmness of the paint film. After the modified epoxy resin reacts chemically with the curing agent in component B, it can form a solid paint film structure, which enhances the wear resistance and chemical corrosion resistance of the paint film. The presence of methylphenyl dimethoxysilane forms a dense silicon carbon layer on the surface of epoxy resin, improves the residual quality of the resin, and increases the water resistance and color difference stability of the paint film. Through these effects and synergistic effects, in two-component anticorrosive paints, modified epoxy resins can provide comprehensive performance, making the paint film have excellent anticorrosion ability and service life.

[0010] Preferably, the epoxy value of the deacrylated rosin-based ethylene glycol diglycidyl ester is 0.204 mol / 100 g, and the hydroxyl value is 0.36 mol / 100 g.

[0011] Preferably, the preparation method of the modified pigment and filler comprises the following steps:

[0012] S41, adding 90 parts of silane coupling agent and 140 parts of linoleic acid into a reactor according to their weight parts, and then heating to 98° C. and stirring, measuring the acid value during the reaction, and stopping the reaction until the acid value is less than 8 mgKOH / g to obtain a linoleic acid-modified silane coupling agent;

[0013] S42, according to the mass fractions, add 70 parts of anhydrous ethanol and 10 parts of deionized water into the reactor and mix them evenly, then dropwise add glacial acetic acid, adjust the pH to 6.5, add 10 parts of linoleic acid-modified silane coupling agent, heat to 42° C. and hydrolyze for 6-7 hours to obtain a silane coupling agent hydrolyzed solution;

[0014] S43. Weigh 20 parts of the pigment-filler mixture by mass and add them to the hydrolysis solution of the silane coupling agent. Stir and react at 42°C for 8-10 hours. Then filter the obtained mixed suspension and dry the filtrate in an oven at 110°C for 8-10 hours to obtain a modified pigment-filler.

[0015] By adopting the above technical scheme, modified pigments and fillers play an important role in two-component anticorrosive paints, and their preparation method also highlights their criticality in the performance of the paint film. The main functions and synergistic effects of modified pigments and fillers are as follows: Improving the corrosion resistance of the paint film: Through the dual modification of silane coupling agent and linoleic acid, the modified pigments and fillers can be better compatible and dispersed with epoxy resin, thereby improving the corrosion resistance of the paint film. The uniform dispersion and excellent adhesion of the modified pigments and fillers can enhance the protection of the paint film against external erosion. Increasing the stone impact resistance of the paint film: The addition of modified pigments and fillers makes the paint film more durable, and can effectively protect the metal substrate from damage when it is subjected to external impacts such as stone impact, thereby improving the stone impact resistance of the paint film. Improving the impact resistance of the paint film: After the modified pigments and fillers are double-modified, the particles in the paint film are more solid and tough, which can slow down the damage of external impact to the paint film and effectively improve the impact resistance of the paint film. Ensure the color and color difference stability of the paint film: The modified pigments and fillers improve the color uniformity and color stability of the paint film through compatibility with epoxy resin, avoiding color changes under different environmental conditions, so that the two-component anti-corrosion paint can continue to maintain a good appearance during use. Through the role and synergy of modified pigments and fillers in the paint film, the two-component anti-corrosion paint can give full play to its advantages, provide excellent corrosion resistance, stone impact resistance, impact resistance and color and color difference stability, and ensure that the metal surface is well protected for a long time.

[0016] Preferably, the silane coupling agent is composed of γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and isocyanatemethyltriethoxysilane in a mass ratio of 5:2:1-2.

[0017] By adopting the above technical scheme, the silane coupling agent is composed of γ-aminopropyl triethoxysilane, 3-aminopropyl trimethoxysilane and isocyanate methyl triethoxysilane, and has multiple functional groups. It can form a strong chemical bond with pigments and epoxy resins, enhance the bonding and compatibility between them, and thus improve the adhesion and stability of the paint film. Improve the anti-stone impact performance of the paint film: The silane coupling agent strengthens the adhesion between the modified pigments and the paint film matrix, increases the hardness and wear resistance of the paint film surface, makes the paint film more resistant to stone impact, and can effectively protect the metal substrate from external damage. Enhance the impact resistance of the paint film: The use of silane coupling agents helps to improve the toughness and elasticity of the paint film, so that it has better impact resistance, reduces the degree of damage to the paint film caused by external impact, and thus effectively protects the metal surface from damage. The silane coupling agent forms good compatibility and bonding with the modified pigments and epoxy resins, so that they can work together to improve the performance of the paint film. The introduction of silane coupling agent can optimize the combination of modified pigments and fillers with the paint film matrix, increase the corrosion resistance, stone chip resistance, and impact resistance of the paint film, and ensure the color stability of the paint film.

[0018] Preferably, the color and filler mixture includes the following raw materials, measured by weight: 10 parts of titanium dioxide, 3 parts of mica powder, 20 parts of precipitated barium sulfate, 3 parts of 1250 mesh talc, and 8 parts of anti-rust pigment.

[0019] Preferably, the anti-rust pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:1.

[0020] By adopting the above technical scheme, aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate play an important role as anti-rust pigments in two-component anti-corrosion paints. The phosphate ions in aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate can be adsorbed on the surface of the metal substrate to form a dense passivation film, effectively isolating oxygen and electrolytes in the solution, thereby preventing oxidation and corrosion of the metal. At the same time, the molybdate ions therein can form a layer of oxide film with strong adsorption on the metal surface, which helps to repair the damaged paint film and steel surface and enhance the protective effect. Molybdate ions can compete with chloride ions in salt spray for adsorption, reduce the corrosion effect of chloride ions on the metal surface, and improve the anti-corrosion effect. Aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate can form a synergistic effect and enhance the anti-corrosion effect of each other. After the two are combined, they can better prevent oxidation and corrosion of the metal surface and have stronger protective performance. In summary, the role of aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in two-component anti-corrosion paint is mainly to provide anti-corrosion protection and reduce chloride ion corrosion. At the same time, they have a synergistic effect, promote each other, and jointly enhance the anti-corrosion effect, thereby protecting the metal surface from corrosion and damage.

[0021] Preferably, the curing agent is curing agent 377H produced by Dofu New Materials (Huizhou) Co., Ltd.; and the solvent is diluent 300T produced by Dofu New Materials (Huizhou) Co., Ltd.

[0022] Preferably, the defoamer is the defoamer Airex902W produced by Digo (China) Co., Ltd.; the leveling agent is the leveling agent BYK381 produced by BYK Chemical (China) Co., Ltd.; the dispersant is the dispersant BYK190 produced by BYK Chemical (China) Co., Ltd.; the wetting agent is the wetting agent BYK346 produced by BYK Chemical (China) Co., Ltd.; and the thickener is the thickener ViscoPlus3030 produced by Digo (China) Co., Ltd.

[0023] In a second aspect, the present application provides a method for preparing a two-component anticorrosive paint, using the following technical solution:

[0024] As a general technical concept, the present application also provides a method for preparing the above-mentioned two-component anticorrosive paint, comprising the following steps: S101, preparation of component A: adding modified epoxy resin, modified pigment filler, dispersant, leveling agent, wetting agent, defoamer, thickener and solvent to a stirring kettle according to their mass fractions, setting the speed to 500 rpm, stirring for 30-40 minutes, and obtaining component A;

[0025] S102, preparation of component B: adding the curing agent and the solvent into a stirring kettle according to the mass fractions, setting the speed to 300 rpm, stirring for 8-10 minutes, and obtaining component B;

[0026] S103, mixing the prepared components A and B in a mass ratio of 1:1 to obtain a two-component anticorrosive paint.

[0027] In summary, the beneficial technical effects of this application are:

[0028] 1. Good water resistance: Modified epoxy resin and added methylphenyl dimethoxysilane can improve the water resistance of the paint film, so that the two-component anti-corrosion paint can still maintain good anti-corrosion effect in a humid environment.

[0029] 2. Excellent corrosion resistance: The phosphate ions and molybdate ions in the anti-rust pigment can be effectively adsorbed on the surface of the metal substrate to form a dense passivation and oxide film, effectively preventing metal oxidation and corrosion.

[0030] 3. Fast drying speed: The modified pigments and fillers have good dispersibility, which enables the paint film to dry more quickly and improve production efficiency.

[0031] 4. Good stone impact resistance: The high temperature heat resistance and stone impact resistance of the modified epoxy resin are improved, so that the two-component anti-corrosion paint can withstand external impact and is not easily damaged.

[0032] 5. Good impact resistance: After double modification, the modified pigments and fillers have improved their compatibility with epoxy resin, enhanced the impact resistance of the two-component anti-corrosion paint, and made the paint film more durable.

[0033] 6. High color difference stability: The addition of modified pigments and fillers improves the color difference stability of the paint film, making the coating effect of the two-component anti-corrosion paint more uniform. DETAILED DESCRIPTION

[0034] The implementation scheme of the present application will be described in detail below in conjunction with the examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be regarded as limiting the scope of the present application. If the specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially. Some of the raw materials used in the following examples are: the curing agent is the curing agent 377H of Dofu New Materials (Huizhou) Co., Ltd.; the solvent is the diluent 300T of Dofu New Materials (Huizhou) Co., Ltd.; the defoamer is the defoamer Airex902W of Digo (China) Co., Ltd.; the leveling agent is the leveling agent BYK381 of BYK Chemical (China) Co., Ltd.; the dispersant is the dispersant BYK190 of BYK Chemical (China) Co., Ltd.; the wetting agent is the wetting agent BYK346 of BYK Chemical (China) Co., Ltd.; the thickener is the thickener ViscoPlus3030 of Digo (China) Co., Ltd.

[0035] Preparation Example 1 Preparation of modified epoxy resin

[0036] The preparation method of the modified epoxy resin is as follows: according to the mass fractions, 4 kg of methylphenyl dimethoxysilane and 10 kg of rosin-based ethylene glycol diglycidyl acrylate (epoxy value is 0.204 mol / 100 g, hydroxyl value is 0.36 mol / 100 g) are added into a four-mouth reactor equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen conduit, and 0.02 kg of a catalyst tetraisopropyl titanate is added at the same time. After nitrogen is passed for 15-20 minutes, stirring is started, and the temperature is raised to 115° C. and the reaction is carried out for 4.5 hours under heat preservation to obtain the modified epoxy resin.

[0037] The modified epoxy resin prepared above was applied to each embodiment.

[0038] Preparation Example 2 Preparation of modified pigments and fillers

[0039] The preparation method of the modified pigment and filler comprises the following steps:

[0040] S41. Add 9 kg of silane coupling agent and 14 kg of linoleic acid into a reactor according to their mass fractions, and then heat to 98° C. and stir. During the reaction, measure the acid value until the acid value is less than 8 mgKOH / g to stop the reaction, and obtain a linoleic acid-modified silane coupling agent, wherein the silane coupling agent is composed of γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and isocyanatemethyltriethoxysilane in a mass fraction ratio of 5:2:1.

[0041] S42, according to the mass fractions, add 7 kg of anhydrous ethanol and 1 kg of deionized water into the reactor and mix them evenly, then drop glacial acetic acid, adjust the pH to 6.5, add 1 kg of linoleic acid-modified silane coupling agent, heat to 42° C. and hydrolyze for 6 hours to obtain a silane coupling agent hydrolyzed solution;

[0042] S43. Weigh 2 kg of the pigment-filler mixture by mass, add it to the hydrolysis solution of the silane coupling agent, stir and react at 42°C for 8 hours, then filter the obtained mixed suspension, and dry the filtrate in an oven at 110°C for 8 hours to obtain a modified pigment-filler. The pigment-filler mixture, by mass, includes the following raw materials: 1 kg of titanium dioxide, 0.3 kg of mica powder, 2 kg of precipitated barium sulfate, 0.3 kg of 1250 mesh talc, and 0.8 kg of rust-proof pigment. The rust-proof pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:1.

[0043] Preparation Example 3 Preparation of modified pigments and fillers

[0044] The preparation method of the modified pigment and filler comprises the following steps:

[0045] S41. Add 9 kg of silane coupling agent and 14 kg of linoleic acid into a reactor according to their mass fractions, heat to 98° C. and stir, measure the acid value during the reaction, and stop the reaction until the acid value is less than 8 mgKOH / g to obtain a linoleic acid-modified silane coupling agent, wherein the silane coupling agent is composed of γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and isocyanatemethyltriethoxysilane in a mass fraction ratio of 5:2:2;

[0046] S42, according to the mass fractions, add 7 kg of anhydrous ethanol and 1 kg of deionized water into the reactor and mix them evenly, then drop glacial acetic acid, adjust the pH to 6.5, add 1 kg of linoleic acid-modified silane coupling agent, heat to 42° C. and hydrolyze for 7 h to obtain a silane coupling agent hydrolyzed solution;

[0047] S43. Weigh 2 kg of the pigment-filler mixture by mass, add it to the hydrolysis solution of the silane coupling agent, stir and react at 42°C for 10 hours, then filter the obtained mixed suspension, and place the filtrate in an oven at 110°C to dry for 10 hours to obtain a modified pigment-filler. The pigment-filler mixture, by mass, includes the following raw materials: 1 kg of titanium dioxide, 0.3 kg of mica powder, 2 kg of precipitated barium sulfate, 0.3 kg of 1250 mesh talc, and 0.8 kg of rust-proof pigment. The rust-proof pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:1.

[0048] Preparation Example 4 Preparation of modified pigments and fillers

[0049] The preparation method of the modified pigment and filler comprises the following steps:

[0050] S41. Add 9 kg of silane coupling agent and 14 kg of linoleic acid into a reactor according to their mass fractions, heat to 98° C. and stir, measure the acid value during the reaction, and stop the reaction until the acid value is less than 8 mgKOH / g to obtain a linoleic acid-modified silane coupling agent, wherein the silane coupling agent is composed of γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and isocyanatemethyltriethoxysilane in a mass fraction ratio of 5:2:1.5;

[0051] S42, according to the mass fractions, add 7 kg of anhydrous ethanol and 1 kg of deionized water into the reactor and mix them evenly, then drop glacial acetic acid, adjust the pH to 6.5, add 1 kg of linoleic acid-modified silane coupling agent, heat to 42° C. and hydrolyze for 6 hours to obtain a silane coupling agent hydrolyzed solution;

[0052] S43. Weigh 2 kg of the pigment-filler mixture by mass, add it to the hydrolysis solution of the silane coupling agent, stir and react at 42°C for 9 hours, then filter the obtained mixed suspension, and dry the filtrate in an oven at 110°C for 9 hours to obtain a modified pigment-filler. The pigment-filler mixture, by mass, includes the following raw materials: 1 kg of titanium dioxide, 0.3 kg of mica powder, 2 kg of precipitated barium sulfate, 0.3 kg of 1250 mesh talc, and 0.8 kg of rust-proof pigment. The rust-proof pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:1.

[0053] Preparation of Comparative Example 1: Preparation of Modified Pigments and Fillers

[0054] The same as Preparation Example 4, except that the silane coupling agent is γ-aminopropyltriethoxysilane.

[0055] Preparation of Comparative Example 2: Preparation of Modified Pigments and Fillers

[0056] The same as Preparation Example 4, except that the silane coupling agent is 3-aminopropyltrimethoxysilane.

[0057] Preparation of Comparative Example 3: Preparation of Modified Pigments and Fillers

[0058] The same as Preparation Example 4, except that the silane coupling agent is isocyanate methyl triethoxy silane.

[0059] Preparation of Comparative Example 4: Preparation of Modified Pigments and Fillers

[0060] The same as Preparation Example 4, except that the anti-rust pigment is aluminum zinc phosphomolybdate.

[0061] Preparation of Comparative Example 5 Preparation of Modified Pigments and Fillers

[0062] The same as Preparation Example 4, except that the anti-rust pigment is basic zinc molybdenum phosphate.

[0063] Example 1

[0064] A two-component anticorrosive paint, comprising a component A and a component B, wherein the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials by mass: 5.0 kg of modified epoxy resin, 3.5 kg of modified pigments and fillers, 0.2 kg of dispersant, 0.02 kg of leveling agent, 0.01 kg of wetting agent, 0.03 kg of defoamer, 0.05 kg of thickener, and 3.0 g of solvent; the component B comprises the following raw materials by mass: 0.8 kg of curing agent and 1.0 kg of solvent, and the modified pigments and fillers are the modified pigments and fillers prepared in Preparation Example 2;

[0065] The method for preparing the above-mentioned two-component anticorrosive paint comprises the following steps:

[0066] S101, preparation of component A: add modified epoxy resin, modified pigment filler, dispersant, leveling agent, wetting agent, defoamer, thickener and solvent to a stirring kettle according to their weight proportions, set the speed to 500 rpm, stir for 30 minutes, and obtain component A;

[0067] S102, preparation of component B: adding the curing agent and the solvent into a stirring kettle according to the mass fractions, setting the speed to 300 rpm, stirring for 8 minutes, and obtaining component B;

[0068] S103, mixing the prepared components A and B in a mass ratio of 1:1 to obtain a two-component anticorrosive paint.

[0069] Example 2

[0070] A two-component anticorrosive paint, comprising a component A and a component B, wherein the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials by mass: 5.5 kg of modified epoxy resin, 4.0 kg of modified pigments and fillers, 0.25 kg of dispersant, 0.04 kg of leveling agent, 0.03 kg of wetting agent, 0.05 kg of defoamer, 0.08 kg of thickener, and 5.0 kg of solvent; the component B comprises the following raw materials by mass: 1.0 kg of curing agent and 1.5 kg of solvent, and the modified pigments and fillers are the modified pigments and fillers prepared in Preparation Example 3;

[0071] The method for preparing the above-mentioned two-component anticorrosive paint comprises the following steps:

[0072] S101, preparation of component A: add modified epoxy resin, modified pigment filler, dispersant, leveling agent, wetting agent, defoamer, thickener and solvent to a stirring kettle according to their weight fractions, set the speed to 500 rpm, stir for 40 minutes, and obtain component A;

[0073] S102, preparation of component B: adding the curing agent and the solvent into a stirring kettle according to the mass fractions, setting the speed to 300 rpm, stirring for 10 minutes, and obtaining component B;

[0074] S103, mixing the prepared components A and B in a mass ratio of 1:1 to obtain a two-component anticorrosive paint.

[0075] Example 3

[0076] A two-component anticorrosive paint, comprising a component A and a component B, wherein the mass ratio of the component A to the component B is 1:1; the component A comprises the following raw materials by mass: 5.3 kg of modified epoxy resin, 3.8 kg of modified pigments and fillers, 0.23 kg of dispersant, 0.03 kg of leveling agent, 0.02 kg of wetting agent, 0.04 kg of defoamer, 0.06 kg of thickener, and 4.0 kg of solvent; the component B comprises the following raw materials by mass: 0.9 kg of curing agent and 1.2 kg of solvent, and the modified pigments and fillers are the modified pigments and fillers prepared in Preparation Example 4;

[0077] The method for preparing the above-mentioned two-component anticorrosive paint comprises the following steps:

[0078] S101, preparation of component A: add modified epoxy resin, modified pigment filler, dispersant, leveling agent, wetting agent, defoamer, thickener and solvent to a stirring kettle according to their weight fractions, set the speed to 500 rpm, stir for 35 minutes, and obtain component A;

[0079] S102, preparation of component B: adding the curing agent and the solvent into a stirring kettle according to the mass fractions, setting the rotation speed to 300 rpm, stirring for 9 minutes, and obtaining component B;

[0080] S103, mixing the prepared components A and B in a mass ratio of 1:1 to obtain a two-component anticorrosive paint.

[0081] Comparative Example 1

[0082] The same as Example 3, except that an equal amount of bisphenol A epoxy resin E-44 is used to replace the modified epoxy resin prepared in Preparation Example 1 of the present application.

[0083] Comparative Example 2

[0084] The same as Example 3, except that the modified pigment and filler are the modified pigment and filler prepared in Comparative Example 1.

[0085] Comparative Example 3

[0086] The same as Example 3, except that the modified pigment and filler are the modified pigment and filler prepared in Comparative Example 2.

[0087] Comparative Example 4

[0088] The same as Example 3, except that the modified pigment and filler are the modified pigment and filler prepared in Comparative Example 3.

[0089] Comparative Example 5

[0090] The same as Example 3, except that the modified pigment and filler are the modified pigment and filler prepared in Comparative Example 4.

[0091] Comparative Example 6

[0092] The same as Example 3, except that the modified pigment and filler are the modified pigment and filler prepared in Comparative Example 5.

[0093] Performance Testing

[0094] The two-component anticorrosive paints prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were sampled and sprayed onto 5 cm x 5 cm x 0.2 cm iron plate samples (marked as base samples) that had been dipped in primer, and forced dried at low temperature (80°C / 30min). After standing for 3 days, the following performance tests were performed. The test results are shown in Table 1.

[0095] Surface drying time: measured according to the provisions of GB / T 1728-2020;

[0096] Adhesion: Use the 100-grid method to test adhesion, and use a magnifying glass to observe whether the cut part of the coating is smooth and has not fallen off;

[0097] Neutral salt spray resistance: measured in accordance with the provisions of GB / T1771-2007;

[0098] Impact resistance: According to GB / T1732-2007, the weight height is 50cm, whether it is positive impact or negative impact, observe whether the coating is damaged;

[0099] Color difference △E: measured in accordance with the provisions of GB / T11186.3-1989;

[0100] Stone impact resistance: measured in accordance with the provisions of GB / T9753-2007;

[0101] Water resistance: Determined in accordance with the provisions of GB / T1733-1933, soaked at 40℃, no bubbles, no rust for the specified time.

[0102] Table 1 Performance test

[0103]

[0104]

[0105] Analyzing the data in Table 1, we can see that:

[0106] 1) The two-component anti-corrosion paints prepared in Examples 1 to 3 have the advantages of good water resistance, excellent corrosion resistance, fast drying speed, good stone impact resistance, good impact resistance and high color difference stability.

[0107] 2) The performance comparison analysis of the two-component anticorrosive paint prepared in Example 3 and Comparative Example 1 shows that the modified epoxy resin prepared by the present application can form a dense paint film surface due to the structure of the modified epoxy resin rich in silicon carbon layer, thereby improving the waterproof performance of the paint film and preventing the corrosion of the metal substrate by water. The modified epoxy resin can maintain the stability of the paint film at high temperature, enhance the bonding between the resin and the substrate, and improve the wear resistance and impact resistance of the paint film. Compatibility with modified pigments and fillers improves corrosion resistance: The modified epoxy resin improves the corrosion resistance of the paint film through interaction with the modified pigments and fillers, so that the pigments and fillers in the paint film can be better covered on the metal surface, increasing the adhesion and firmness of the paint film. The presence of methylphenyldimethoxysilane forms a dense silicon carbon layer on the surface of the epoxy resin, improves the residual mass of the resin, and increases the water resistance and color difference stability of the paint film.

[0108] 3) The performance comparison analysis of the two-component anticorrosive paint prepared in combination with Example 3 and Comparative Examples 2-4 shows that the silane coupling agent is composed of γ-aminopropyl triethoxysilane, 3-aminopropyl trimethoxysilane and isocyanate methyl triethoxysilane in a mass ratio of 5:2:1.5, has multiple functional groups, can form a strong chemical bond with pigments and epoxy resins, enhance the bonding and compatibility between them, thereby improving the adhesion and stability of the paint film. Improve the stone impact resistance of the paint film: The silane coupling agent strengthens the adhesion between the modified pigments and the paint film matrix, increases the hardness and wear resistance of the paint film surface, makes the paint film more resistant to stone impact, and can effectively protect the metal substrate from external damage. Enhance the impact resistance of the paint film: The use of silane coupling agents helps to improve the toughness and elasticity of the paint film, so that it has better impact resistance, reduces the degree of damage to the paint film caused by external impact, and thus effectively protects the metal surface from damage. Silane coupling agent has good compatibility and bonding with modified pigments and fillers and epoxy resin, which enables them to work together to improve the performance of the paint film. The introduction of silane coupling agent can optimize the bonding between modified pigments and fillers and the paint film matrix, increase the corrosion resistance, stone impact resistance and impact resistance of the paint film, and ensure the stability of the paint film color.

[0109] 4) The performance comparison analysis of the two-component anticorrosive paint prepared in combination with Example 3 and Comparative Examples 5-6 shows that the rust-proof pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:1. The phosphate ions in aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate can be adsorbed on the surface of the metal substrate to form a dense passivation film, which effectively isolates oxygen and electrolytes in the solution, thereby preventing oxidation and corrosion of the metal. At the same time, the molybdate ions therein can form a layer of highly adsorbable oxide film on the metal surface, which helps to repair the damaged paint film and steel surface, and plays an enhanced protective role. The molybdate ions can compete with the chloride ions in the salt spray for adsorption, reduce the corrosion of the chloride ions on the metal surface, and improve the anticorrosion effect. Aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate can form a synergistic effect and strengthen the anticorrosion effect. After the two are combined, oxidation and corrosion of the metal surface can be better prevented, and stronger protective performance is obtained.

[0110] The above embodiments are only used to explain the technical solutions of the present application rather than to limit them. Although the above embodiments provide a specific description of the present application, relevant technical personnel should understand that the specific implementation modes of the present invention can still be modified or replaced by equivalents, and any modifications and equivalent replacements that do not depart from the spirit and scope of the present application should be included in the scope of protection of the present application.

Claims

1. A two-component anticorrosive paint, characterized in that: The invention comprises component A and component B, wherein the mass ratio of component A to component B is 1:1; the component A comprises the following raw materials by mass: 50-55 parts of modified epoxy resin, 35-40 parts of modified pigment and filler, 2-2.5 parts of dispersant, 0.2-0.4 parts of leveling agent, 0.1-0.3 parts of wetting agent, 0.3-0.5 parts of defoamer, 0.5-0.8 parts of thickener, and 30-50 parts of solvent; the component B comprises the following raw materials by mass: 8-10 parts of curing agent and 10-15 parts of solvent; The preparation method of the modified epoxy resin is as follows: 4 parts by mass of methylphenyl dimethoxysilane and 10 parts of rosin-based ethylene glycol diglycidyl acrylate are added to a four-mouth reactor equipped with a stirrer, a thermometer, a reflux condenser and a nitrogen conduit, and 0.02 parts of a catalyst, tetraisopropyl titanate, are added at the same time, nitrogen is passed through for 15-20 minutes, stirring is started, the temperature is raised to 110-120° C., and the reaction is carried out for 4-5 hours under heat preservation to obtain the modified epoxy resin; The preparation method of the modified pigment and filler comprises the following steps: S41. Add 90 parts of silane coupling agent and 140 parts of linoleic acid into a reactor according to their mass fractions, and then heat to 98° C. and stir. During the reaction, measure the acid value until the acid value is less than 8 mgKOH / g to stop the reaction, and obtain a linoleic acid-modified silane coupling agent; wherein the silane coupling agent is composed of γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and isocyanatemethyltriethoxysilane in a mass fraction ratio of 5:2:1-2; S42, according to the mass fractions, add 70 parts of anhydrous ethanol and 10 parts of deionized water into the reactor and mix them evenly, then dropwise add glacial acetic acid, adjust the pH to 6.5, add 10 parts of linoleic acid-modified silane coupling agent, heat to 42° C. and hydrolyze for 6-7 hours to obtain a silane coupling agent hydrolyzed solution; S43, weighing 20 parts of the pigment-filler mixture according to the mass fraction, adding them to the hydrolyzed solution of the silane coupling agent, stirring and reacting at 42° C. for 8-10 hours, then filtering the obtained mixed suspension, and drying the filtrate in an oven at 110° C. for 8-10 hours to obtain a modified pigment-filler; The pigment and filler mixture comprises the following raw materials by weight: 10 parts of titanium dioxide, 3 parts of mica powder, 20 parts of precipitated barium sulfate, 3 parts of 1250 mesh talc, and 8 parts of anti-rust pigment; The anti-rust pigment is prepared by mixing aluminum zinc phosphomolybdate and basic zinc molybdenum phosphate in a mass ratio of 3:

1.

2. A two-component anticorrosive paint according to claim 1, characterized in that: The epoxy value of the rosin-based ethylene glycol diglycidyl acrylate is 0.204 mol / 100 g, and the hydroxyl value is 0.36 mol / 100 g.

3. A two-component anticorrosive paint according to claim 1, characterized in that: The curing agent is curing agent 377H produced by Dofu New Materials (Huizhou) Co., Ltd.; the solvent is diluent 300T produced by Dofu New Materials (Huizhou) Co., Ltd.

4. A two-component anticorrosive paint according to claim 1, characterized in that: The defoaming agent is the defoaming agent Airex902W produced by Digo (China) Co., Ltd.; the leveling agent is the leveling agent BYK381 produced by BYK Chemical (China) Co., Ltd.; the dispersant is the dispersant BYK190 produced by BYK Chemical (China) Co., Ltd.; the wetting agent is the wetting agent BYK346 produced by BYK Chemical (China) Co., Ltd.; and the thickener is the thickener ViscoPlus3030 produced by Digo (China) Co., Ltd.

5. A method for preparing a two-component anticorrosive paint according to any one of claims 1 to 4, characterized in that: The following steps are involved: S101, preparation of component A: add modified epoxy resin, modified pigment filler, dispersant, leveling agent, wetting agent, defoamer, thickener and solvent to a stirring kettle according to their weight fractions, set the speed to 500 rpm, stir for 30-40 minutes, and obtain component A; S102, preparation of component B: adding the curing agent and the solvent into a stirring kettle according to the mass fractions, setting the speed to 300 rpm, stirring for 8-10 minutes, and obtaining component B; S103, mixing the prepared components A and B in a mass ratio of 1:1 to obtain a two-component anticorrosive paint.

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