Water-based quick-drying coating for corrosion prevention of aluminum alloy substrate and preparation method of water-based quick-drying coating

Abstract

The invention relates to the technical field of coating preparation, and particularly discloses a water-based quick-drying coating for corrosion prevention of an aluminum alloy substrate and a preparation method of the water-based quick-drying coating. Comprising the following raw materials in parts by weight: 28-40 parts of a water-borne epoxy resin emulsion curing agent, 56-78 parts of a water-borne epoxy prepolymer component, 14-18 parts of functional filler, 0.5-1.3 parts of a defoaming agent, 0.6-1.4 parts of a flatting agent, 0.8-1.6 parts of a wetting dispersant and 3-7 parts of a curing accelerator, the waterborne epoxy prepolymer component and the functional filler are added into the coating, and the waterborne epoxy prepolymer component contains active hydroxyl, imidazolinyl, a flexible long-chain alkane structure, a-Si-O-Me-bond and a benzene ring, not only can participate in a curing reaction of the epoxy coating, but also can be chemically crosslinked with the functional filler, so that the functional filler can be cured, and the water-borne epoxy prepolymer component can be cured. The weather resistance and the mechanical property of the coating are further improved while the waterproof performance of the coating is improved.

Description

Technical Field

[0001] The present application relates to the technical field of coating preparation, and more specifically, to a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates and a preparation method thereof. Background Art

[0002] Water-based quick-drying paint uses physical and chemical methods to evenly disperse the paint in water to form a uniform and stable water-in-oil emulsion system. Among them, water-based epoxy resin has the advantages of high adhesion, heat resistance, corrosion resistance and convenient construction. It is widely used in building structure engineering, mechanical parts processing and aviation industry manufacturing.

[0003] Epoxy resin coatings are usually used to protect metals from corrosion in corrosive environments. However, when pure epoxy resin coatings are directly applied to metal corrosion protection, their tight three-dimensional network structure is prone to produce micropores and cracks, resulting in brittle fracture of the coating, thereby reducing the mechanical properties of the coating. The existing technology often improves its defects by adding nanoclay materials. However, due to their small size and high specific surface area, nanoclay materials are prone to agglomeration in epoxy resins, resulting in uneven dispersion. At the same time, the compatibility between nanoclay materials and coatings is poor, resulting in poor mechanical properties and weather resistance of epoxy coatings. In addition, epoxy resins themselves have defects such as insufficient flexibility and poor UV aging resistance. In addition, hydrophilic groups or emulsifiers are introduced during the water-based process, resulting in reduced waterproof performance of the prepared coating.

[0004] Therefore, providing a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates with high mechanical properties, good weather resistance and good waterproof performance is a technical problem that needs to be solved at present. Summary of the invention

[0005] In order to solve the problems mentioned in the above background technology, the present application provides a water-based quick-drying coating for corrosion protection of aluminum alloy substrates and a preparation method thereof.

[0006] A water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28-40 parts of a water-based epoxy resin emulsion curing agent, 56-78 parts of a water-based epoxy prepolymer component, 14-18 parts of a functional filler, 0.5-1.3 parts of a defoamer, 0.6-1.4 parts of a leveling agent, 0.8-1.6 parts of a wetting dispersant, and 3-7 parts of a curing accelerator; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional fillers, water-based epoxy resin emulsion curing agent, leveling agent, wetting dispersant, defoaming agent and curing accelerator are added to the water-based epoxy prepolymer component under stirring, and the mixture is stirred evenly to obtain a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0007] Preferably, the curing agent for the waterborne epoxy resin emulsion is dicyandiamide or diaminodiphenyl sulfone.

[0008] Preferably, the defoaming agent is at least one of Foamex-815, Foamex-8030 and BYK-024.

[0009] Preferably, the leveling agent is BYK-381 or BYK-348.

[0010] Preferably, the wetting and dispersing agent is BYK-346 or BYK-190.

[0011] Preferably, the defoaming agent is at least one of Foamex-815, Foamex-8030 and BYK-024.

[0012] Preferably, the curing accelerator is DMP-30 or K-54.

[0013] Preferably, the method for preparing the waterborne epoxy prepolymer component comprises the following steps: Add epoxy prepolymer and ethanolamine to anhydrous ethanol, stir evenly, heat to 64-70°C, stir and react for 2-3h, add glacial acetic acid dropwise, and control the dripping to be completed within 10min. After the dripping is completed, continue stirring for 0.3-0.6h, then add deionized water, continue stirring and react for 0.4-0.8h to obtain a water-based epoxy prepolymer component, wherein the usage ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water is 2-3:20-30:0.18-0.22:0.06-0.10:35.

[0014] Preferably, the epoxy prepolymer is prepared by the following steps: Step A1, tris(hydroxymethyl)aminomethane and anhydrous DMF are mixed evenly, the temperature is raised to 35-45° C., and a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol is added dropwise while stirring, and the dripping is controlled to be completed within 30 minutes. After the dripping is completed, the temperature is raised to 72-76° C., and the stirring reaction is continued for 4-6 hours. After the reaction is completed, the pH is adjusted to neutral, and the mixture is rotary evaporated, washed, and dried to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and the mixed solution a is 1-2:30-40:15-25, and the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 3.2-5.8:0.08-0.12:20. In the above reaction process, anhydrous DMF is used as a solvent, and the amino group on the tris(hydroxymethyl)aminomethane and the anhydride group on the octadecenylsuccinic anhydride undergo a ring-opening esterification reaction to obtain an unsaturated monomer; Step A2, adding an unsaturated monomer and a platinum catalyst to isopropanol, heating to 30-40°C, stirring evenly, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30 minutes. After the dripping is completed, heating to reflux, continuing to stir and react for 6-8 hours, after the reaction is completed, cooling to room temperature, rotary evaporation, washing, and drying to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the platinum catalyst, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6-12.2:1-2:45-55:0.8-1.8, and in the above reaction process, using isopropanol as a solvent, the unsaturated double bonds on the unsaturated monomer and the active hydrogen on the 1,1,3,3-tetramethyldisiloxane undergo a silylation reaction to obtain the modifier; Step A3, under nitrogen protection, under nitrogen protection, add the modifier and diethylenetriamine to xylene, stir evenly at room temperature, then heat to 145-155 ° C, continue stirring to react for 1.6-2.2h, then heat to 195-205 ° C, continue stirring to react for 2-3h to obtain an imidazoline monomer, after the reaction is completed, cool to 90-100 ° C, add benzyl chloride, heat to reflux reaction for 3-4h, and rotary evaporate to obtain an anticorrosion enhancement component, wherein the modifier, diethylenetriamine, dimethylbenzene The mass ratio of benzene to benzyl chloride is 5-10:0.4-0.8:36-42:0.6-1.1. In the above reaction process, xylene is used as a solvent, and the modifier and diethylenetriamine undergo an amidation reaction, and then undergo a self-condensation reaction at a high temperature to obtain an imidazoline monomer. The amino group on the imidazoline monomer continues to undergo an electrophilic substitution reaction with the active chlorine atom on the benzyl chloride to obtain an anticorrosion enhancement component. The prepared anticorrosion enhancement component contains an active carboxyl group that can continue to participate in subsequent reaction processes.

[0015] Step A4, adding the anticorrosion enhancing component to anhydrous DMF, heating to 45-55°C, stirring evenly, adding epichlorohydrin dropwise, controlling the dripping to be completed within 10 minutes, heating to 64-76°C, stirring and reacting for 6-8 hours, and after the reaction is completed, filtering by suction, washing and drying the filter cake to obtain an epoxy prepolymer, wherein the mass ratio of the anticorrosion enhancing component, anhydrous DMF and epichlorohydrin is 5.4-8.2:30-40:0.72-0.98, and during the reaction, the amount of the anticorrosion enhancing component is controlled to be slightly higher than twice the equivalent of epichlorohydrin, so that the remaining hydroxyl groups on the anticorrosion enhancing component can participate in the subsequent reaction process. In the above reaction process, anhydrous DMF is used as a solvent, and the active hydroxyl groups on the anticorrosion enhancing component undergo an electrophilic substitution reaction with the chlorine atoms on the epichlorohydrin to obtain an epoxy prepolymer.

[0016] Preferably, the platinum catalyst is an isopropanol solution of chloroplatinic acid with a mass fraction of 1%.

[0017] Preferably, the functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution, stirring evenly, heating to 60-80°C, continuing stirring for 1-2h, centrifuging, washing and drying the precipitate to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution, stirring for 10-20min, then adding KH-560, heating to 40-50°C, stirring for reaction for 4-5h, centrifuging, washing and drying the precipitate to obtain pretreated attapulgite, wherein the mass ratio of attapulgite to nitric acid solution is 2-3:40-50, the mass fraction of nitric acid solution is 22-26%, the mass ratio of acidified attapulgite, ethanol aqueous solution and KH-560 is 1-2:22-26:0.3-0.6, the mass fraction of ethanol aqueous solution is 26-30%, firstly using a nitric acid solution to perform a first treatment on the attapulgite to remove impurities and increase internal pores, and then using KH-560 for modification treatment so that its surface is rich in epoxy groups, siloxane groups and the like; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, drip tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF mixed solution b, and control the dripping to be completed within 10 minutes. After the dripping is completed, the temperature is raised to 100-110°C, and the reaction is stirred for 2-3 hours. After the reaction is completed, centrifugation is performed, and the precipitate is washed and dried to obtain a functional filler, wherein the mass ratio of the pretreated attapulgite, anhydrous DMF and the mixed solution b is 1.6-2.0:40-50:25-35, and the mass ratio of tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF in the mixed solution b is 0.04:0.4-0.6:16-20. In the above reaction process, anhydrous DMF is used as a solvent, and the epoxy group on the pretreated attapulgite undergoes a ring-opening reaction with 6-aminopyridine-2-carboxylic acid to obtain a functional filler.

[0018] Compared with the prior art, the present invention has the following beneficial effects: in order to improve the weather resistance and waterproofness of water-based quick-drying coatings, the present invention starts from two aspects. First, a water-based epoxy prepolymer component is added to the coating raw material. The water-based epoxy prepolymer component contains active hydroxyl groups, imidazoline groups, flexible long-chain alkane structures, -Si-O-Me- bonds and benzene rings. On the one hand, the active hydroxyl groups can undergo a cross-linking reaction with the curing agent in the base material to improve the cross-linking degree of the coating system, strengthen the intermolecular binding force, and make it difficult for water molecules to enter the interior of the molecules through the coating film, thereby improving the waterproof performance of the coating. On the other hand, as an anchor point, the active hydroxyl groups undergo a ring-opening reaction with the epoxy groups of the functional fillers to further improve the cross-linking degree and improve the mechanical properties of the water-based quick-drying coating. On the one hand, the imidazoline groups can form coordination bonds with the atoms on the metal surface, tightly adhere to the metal surface, and improve the weather resistance of the coating. On the other hand, they can act as anchors to generate multiple bonds with the surface of the functional fillers. Point adsorption is combined to improve the dispersion stability of the functional filler. The presence of the flexible long-chain alkane structure can be entangled with the molecular chain in the base material and the flexible structure in the functionalized filler to form a mutually entangled molecular interpenetrating network structure, further improving the mechanical properties of the coating. The presence of the -Si-O-Me- bond, on the one hand, improves the mechanical properties of the coating together with the rigid benzene ring, and on the other hand, it exerts the hydrophobicity and weather resistance of the organic siloxane, further improving the hydrophobicity and weather resistance of the water-based quick-drying coating; secondly, the addition of functional fillers, on the one hand, exerts the UV resistance of attapulgite to improve the weather resistance of the coating, and on the other hand, the 6-aminopyridine-2-carboxylic acid grafted on the surface of the pre-treated attapulgite has a pyridine group with high rigidity and can produce a stabilizing effect on the aluminum alloy substrate. Introducing it into the water-based quick-drying coating can work synergistically with the water-based epoxy prepolymer component to jointly improve the mechanical properties, weather resistance and waterproof properties of the water-based quick-drying coating. DETAILED DESCRIPTION

[0019] In order to make the implementation methods of the present application easier to understand, the present application will be described in detail below in conjunction with specific examples. These examples are only for illustration and are not limited to the scope of application of the present application.

[0020] The present application is further described in detail below with reference to the embodiments.

[0021] Preparation Examples 1-3 and Comparative Preparation Examples 1-3 provide methods for preparing epoxy prepolymers.

[0022] Preparation Example 1 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 600 rpm for 30 min until uniform, heating to 35° C., adding a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 72° C., maintaining the rotation speed unchanged, and continuing to stir and react for 4 h. After the reaction is completed, adjusting the pH to neutral with 0.6M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 75° C. to remove anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 3 times in sequence, and drying at 50° C. to constant weight to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1:30:15, and the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 3.2:0.08:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 30°C, controlling the speed to be 500rpm and stirring for 40min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the speed unchanged, and continuing to stir and react for 6h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to be 65°C to remove isopropanol, washing with anhydrous ethanol and deionized water three times in sequence, and then drying at 55°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6:1:45:0.8; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, control the speed at 1000 rpm at room temperature and stir for 10 minutes until uniform, adjust the speed to 550 rpm, then heat to 145°C, continue stirring and reacting for 1.6 hours, then heat to 195°C, continue stirring and reacting for 2 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 90°C, add benzyl chloride, heat to reflux for 3 hours, control the rotary evaporation temperature to 82°C to remove xylene, wash with anhydrous ethanol and deionized water three times in sequence, and then dry at 60°C to constant weight to obtain an anticorrosion enhancement component, wherein the mass ratio of the modifier, diethylenetriamine, xylene and benzyl chloride is 5:0.4:36:0.6; Step A4, add the anti-corrosion enhancement component to anhydrous DMF, heat it to 45°C, control the speed to 700rpm and stir for 20min until it is uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, and after the dripping is completed, heat it to 64°C, maintain the speed unchanged, stir and react for 6h. After the reaction is completed, filter it with suction, wash the filter cake with anhydrous ethanol and deionized water for 3 times, and then dry it at 70°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancement component, anhydrous DMF and epichlorohydrin is 5.4:30:0.72.

[0023] Preparation Example 2 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 650 rpm for 25 min until uniform, heating to 40° C., adding a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 74° C., and stirring and reacting for 5 h. After the reaction is completed, adjusting the pH to neutral with 0.8 M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 80° C. to remove the anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 4 times in sequence to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1.5:35:20, and the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 4.5:0.10:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 35°C, controlling the rotation speed to 550rpm and stirring for 35min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the rotation speed unchanged, and continuing to stir and react for 7h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to 65°C to remove isopropanol, washing with anhydrous ethanol and deionized water for 4 times in sequence, and then drying at 60°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 8.9:1.5:50:1.3; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, control the speed at 1100 rpm at room temperature and stir for 8 minutes until uniform, adjust the speed to 600 rpm, then heat to 150°C, continue stirring and reacting for 1.9 hours, then heat to 200°C, continue stirring and reacting for 2.5 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 95°C, add benzyl chloride, heat to reflux and react for 3.5 hours, control the rotary evaporation temperature to 84°C to remove xylene, wash with anhydrous ethanol and deionized water in sequence for 4 times, and then dry at 65°C to constant weight to obtain an anticorrosion enhancement component, wherein the mass ratio of the modifier, diethylenetriamine, xylene and benzyl chloride is 7.5:0.6:39:0.85; Step A4, add the anti-corrosion enhancement component to anhydrous DMF, heat it to 50°C, control the speed to 750rpm and stir for 15min until it is uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, heat it to 70°C, maintain the speed unchanged, stir and react for 7h, after the reaction is completed, filter it with suction, wash the filter cake with anhydrous ethanol and deionized water 4 times, and then dry it at 75°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancement component, anhydrous DMF and epichlorohydrin is 6.8:35:0.85.

[0024] Preparation Example 3 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 700 rpm for 20 min until uniform, heating to 45° C., adding a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 76° C., maintaining the rotation speed unchanged, and continuing to stir and react for 6 h. After the reaction is completed, adjusting the pH to neutral with a 1.0 M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 85° C. to remove the anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 5 times in sequence, and drying at 60° C. to constant weight to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 2:40:25, and the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 5.8:0.12:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 40°C, controlling the speed to be 600rpm and stirring for 30min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the speed unchanged, and continuing to stir and react for 8h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to 70°C to remove isopropanol, washing with anhydrous ethanol and deionized water for 5 times in sequence, and then drying at 65°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 12.2:2:55:1.8; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, control the speed at 1200 rpm at room temperature and stir for 6 minutes until uniform, adjust the speed to 650 rpm, then heat to 155°C, continue stirring and reacting for 2.2 hours, then heat to 205°C, continue stirring and reacting for 3 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 100°C, add benzyl chloride, heat to reflux and react for 4 hours, control the rotary evaporation temperature to 86°C to remove xylene, wash with anhydrous ethanol and deionized water for 5 times in sequence, and then dry at 70°C to constant weight, wherein the mass ratio of the modifier, diethylenetriamine, xylene and benzyl chloride is 10:0.8:42:1.1; Step A4, add the anti-corrosion enhancing component to anhydrous DMF, heat it to 55°C, control the speed to 800rpm and stir for 10min until uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, heat it to 76°C, stir and react for 8h, after the reaction is completed, filter it, wash the filter cake with anhydrous ethanol and deionized water 5 times, and then dry it at 80°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancing component, anhydrous DMF and epichlorohydrin is 8.2:40:0.98.

[0025] Comparative Preparation Example 1 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 600 rpm for 30 min until uniform, heating to 35° C., adding a mixed solution a of itaconic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 72° C., maintaining the rotation speed unchanged, and continuing to stir and react for 4 h. After the reaction is completed, adjusting the pH to neutral with 0.6M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 75° C. to remove anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 3 times in sequence, and drying at 50° C. to constant weight to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1:30:15, and the mass ratio of itaconic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 3.2:0.08:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 30°C, controlling the speed to be 500rpm and stirring for 40min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the speed unchanged, and continuing to stir and react for 6h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to be 65°C to remove isopropanol, washing with anhydrous ethanol and deionized water three times in sequence, and then drying at 55°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6:1:45:0.8; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, control the speed at 1000 rpm at room temperature and stir for 10 minutes until uniform, adjust the speed to 550 rpm, then heat to 145°C, continue stirring and reacting for 1.6 hours, then heat to 195°C, continue stirring and reacting for 2 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 90°C, add benzyl chloride, heat to reflux for 3 hours, control the rotary evaporation temperature to 82°C to remove xylene, wash with anhydrous ethanol and deionized water three times in sequence, and then dry at 60°C to constant weight to obtain an anticorrosion enhancement component, wherein the mass ratio of the modifier, diethylenetriamine, xylene and benzyl chloride is 5:0.4:36:0.6; Step A4, add the anti-corrosion enhancement component to anhydrous DMF, heat it to 45°C, control the speed to 700rpm and stir for 20min until it is uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, and after the dripping is completed, heat it to 64°C, maintain the speed unchanged, stir and react for 6h. After the reaction is completed, filter it with suction, wash the filter cake with anhydrous ethanol and deionized water for 3 times, and then dry it at 70°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancement component, anhydrous DMF and epichlorohydrin is 5.4:30:0.72.

[0026] Comparative Preparation Example 2 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 600 rpm for 30 min until uniform, heating to 35° C., adding a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 72° C., maintaining the rotation speed unchanged, and continuing to stir and react for 4 h. After the reaction is completed, adjusting the pH to neutral with 0.6M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 75° C. to remove anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 3 times in sequence, and drying at 50° C. to constant weight to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1:30:15, and the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol in the mixed solution a is 3.2:0.08:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 30°C, controlling the speed to be 500rpm and stirring for 40min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the speed unchanged, and continuing to stir and react for 6h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to be 65°C to remove isopropanol, washing with anhydrous ethanol and deionized water three times in sequence, and then drying at 55°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6:0.4:45:0.8; Step A3, under nitrogen protection, under nitrogen protection, add the modifier and N-butylethylenediamine to xylene, control the speed at 1000rpm at room temperature and stir for 10min until uniform, adjust the speed to 550rpm, then heat to 145°C, continue stirring and reacting for 1.6h, then heat to 195°C, continue stirring and reacting for 2h to obtain an imidazoline monomer, after the reaction is completed, cool to 90°C, add benzyl chloride, heat to reflux for 3h, control the rotary evaporation temperature to 82°C to remove xylene, wash with anhydrous ethanol and deionized water three times in sequence, and then dry at 60°C to constant weight to obtain an anticorrosion enhancement component, wherein the mass ratio of the modifier, N-butylethylenediamine, xylene and benzyl chloride is 5:0.4:36:0.6; Step A4, add the anti-corrosion enhancement component to anhydrous DMF, heat it to 45°C, control the speed to 700rpm and stir for 20min until it is uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, and after the dripping is completed, heat it to 64°C, maintain the speed unchanged, stir and react for 6h. After the reaction is completed, filter it with suction, wash the filter cake with anhydrous ethanol and deionized water for 3 times, and then dry it at 70°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancement component, anhydrous DMF and epichlorohydrin is 5.4:30:0.72.

[0027] Comparative Preparation Example 3 The epoxy prepolymer is prepared by the following steps: Step A1, stirring tris(hydroxymethyl)aminomethane and anhydrous DMF at a rotation speed of 600 rpm for 30 min until uniform, heating to 35° C., adding a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol dropwise while stirring, and controlling the dripping to be completed within 30 min. After the dripping is completed, heating to 72° C., maintaining the rotation speed unchanged, and continuing to stir and react for 4 h. After the reaction is completed, adjusting the pH to neutral with 0.6M hydrochloric acid aqueous solution, controlling the rotary evaporation temperature to 75° C. to remove anhydrous DMF, and then washing with anhydrous ethanol and deionized water for 3 times in sequence, and drying at 50° C. to constant weight to obtain an unsaturated monomer, wherein the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1:30:15, and the mass ratio of octadecenylsuccinic anhydride and isopropanol in the mixed solution a is 3.2:20; Step A2, adding an unsaturated monomer and an isopropanol solution of 1% by mass of chloroplatinic acid to isopropanol, heating to 30°C, controlling the speed to be 500rpm and stirring for 40min until uniform, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30min. After the dripping is completed, heating to reflux, maintaining the speed unchanged, and continuing to stir and react for 6h. After the reaction is completed, cooling to room temperature, controlling the rotary evaporation temperature to be 65°C to remove isopropanol, washing with anhydrous ethanol and deionized water three times in sequence, and then drying at 55°C to constant weight to obtain a modifier, wherein the mass ratio of the unsaturated monomer, the isopropanol solution of 1% by mass of chloroplatinic acid, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6:1:45:0.8; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, control the speed to 1000 rpm at room temperature and stir for 10 minutes until uniform, adjust the speed to 550 rpm, then heat to 145°C, continue stirring and reacting for 1.6 hours, then heat to 195°C, continue stirring and reacting for 2 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 90°C, add chlorododecane, heat to reflux for 3 hours, control the rotary evaporation temperature to 82°C to remove xylene, wash with anhydrous ethanol and deionized water three times in sequence, and then dry at 60°C to constant weight to obtain an anticorrosion enhancement component, wherein the mass ratio of the modifier, diethylenetriamine, xylene and chlorododecane is 5:0.4:36:0.6; Step A4, add the anti-corrosion enhancement component to anhydrous DMF, heat it to 45°C, control the speed to 700rpm and stir for 20min until it is uniform, add epichlorohydrin dropwise, control the dripping to be completed within 10min, and after the dripping is completed, heat it to 64°C, maintain the speed unchanged, stir and react for 6h. After the reaction is completed, filter it with suction, wash the filter cake with anhydrous ethanol and deionized water for 3 times, and then dry it at 70°C to constant weight to obtain an epoxy prepolymer, wherein the mass ratio of the anti-corrosion enhancement component, anhydrous DMF and epichlorohydrin is 5.4:30:0.72.

[0028] Preparation Examples 4-6 and Comparative Preparation Examples 4-6 provide methods for preparing waterborne epoxy prepolymer components.

[0029] Preparation Example 4 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: Add epoxy prepolymer and ethanolamine to anhydrous ethanol, control the speed to 400 rpm and stir for 30 minutes until uniform, raise the temperature to 64°C, maintain the speed unchanged, stir and react for 2 hours, add glacial acetic acid dropwise, control the dripping to be completed within 10 minutes, continue stirring for 0.3 hours, then add deionized water, continue stirring and react for 0.4 hours to obtain a water-based epoxy prepolymer component, wherein the amount ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water is 2:20:0.18:0.06:35.

[0030] Preparation Example 5 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: Add epoxy prepolymer and ethanolamine to anhydrous ethanol, control the speed to 450 rpm and stir for 25 minutes until uniform, raise the temperature to 67°C, maintain the speed unchanged, continue stirring and react for 2.5 hours, add glacial acetic acid dropwise, control the dripping to be completed within 10 minutes, continue stirring for 0.45 hours, then add deionized water, continue stirring and react for 0.6 hours to obtain a water-based epoxy prepolymer component, wherein the amount ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water is 2.5:25:0.20:0.08:35.

[0031] Preparation Example 6 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: Add epoxy prepolymer and ethanolamine to anhydrous ethanol, control the speed to 500 rpm and stir for 20 minutes until uniform, raise the temperature to 70°C, maintain the speed unchanged, continue stirring and react for 3 hours, add glacial acetic acid dropwise, control the dripping to be completed within 10 minutes, continue stirring for 0.6 hours, then add deionized water, continue stirring and react for 0.8 hours to obtain a water-based epoxy prepolymer component, wherein the usage ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water is 3:30:0.22:0.10:35.

[0032] Comparative Preparation Example 4 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: The epoxy prepolymer and ethanolamine prepared in Comparative Preparation Example 1 were added to anhydrous ethanol, and the rotation speed was controlled to be 400 rpm and stirred for 30 minutes until uniform. The temperature was raised to 64°C, the rotation speed was maintained unchanged, and the reaction was stirred for 2 hours. Glacial acetic acid was added dropwise, and the dripping was controlled to be completed within 10 minutes. After the dripping was completed, stirring was continued for 0.3 hours, and deionized water was added. The reaction was continued to stir for 0.4 hours to obtain a water-based epoxy prepolymer component, wherein the amount ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water was 2:20:0.18:0.06:35.

[0033] Comparative Preparation Example 5 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: The epoxy prepolymer and ethanolamine prepared in Comparative Preparation Example 2 were added to anhydrous ethanol, and the rotation speed was controlled to be 400 rpm and stirred for 30 minutes until uniform. The temperature was raised to 64°C, the rotation speed was maintained unchanged, and the reaction was stirred for 2 hours. Glacial acetic acid was added dropwise, and the dripping was controlled to be completed within 10 minutes. After the dripping was completed, stirring was continued for 0.3 hours, and deionized water was added. The reaction was continued to stir for 0.4 hours to obtain a water-based epoxy prepolymer component, wherein the usage ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water was 2:20:0.18:0.06:35.

[0034] Comparative Preparation Example 6 The preparation method of the waterborne epoxy prepolymer component comprises the following steps: The epoxy prepolymer and ethanolamine prepared in Comparative Preparation Example 3 were added to anhydrous ethanol, and the rotation speed was controlled to be 400 rpm and stirred for 30 minutes until uniform. The temperature was raised to 64°C, the rotation speed was maintained unchanged, and the reaction was stirred for 2 hours. Glacial acetic acid was added dropwise, and the dripping was controlled to be completed within 10 minutes. After the dripping was completed, stirring was continued for 0.3 hours, and deionized water was added. The reaction was continued to stir for 0.4 hours to obtain a water-based epoxy prepolymer component, wherein the usage ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water was 2:20:0.18:0.06:35.

[0035] Preparation Examples 7-9 and Comparative Preparation Example 7 provide methods for preparing functional fillers.

[0036] Preparation Example 7 The functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution with a mass fraction of 22%, stirring for 30 minutes at a control speed of 500 rpm until uniform, heating to 60°C, maintaining the speed unchanged, continuing to stir for 1 hour, centrifuging, washing the precipitate with deionized water until the washing liquid is neutral, and then drying at 80°C to constant weight to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution with a mass fraction of 26%, stirring for 10 minutes at a control speed of 600 rpm, then adding KH-560, heating to 40°C, maintaining the speed unchanged, continuing to stir and react for 4 hours, centrifuging, washing the precipitate with deionized water 3 times, and drying at 55°C to constant weight to obtain pretreated attapulgite, wherein the mass ratio of attapulgite to the nitric acid solution with a mass fraction of 22% is 2:40, and the mass ratio of acidified attapulgite, the ethanol aqueous solution with a mass fraction of 22% and KH-560 is 1:22:0.3; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, control the ultrasonic frequency to 40kHz, the ultrasonic power to 600w, the ultrasonic treatment for 30min, drip tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF mixed solution b, control the dripping within 10min, after the dripping, heat to 100°C, control the speed to 600rpm, stir and react for 2h, after the reaction is completed, centrifuge, wash the precipitate with anhydrous ethanol and deionized water 3 times, and then dry it at 50°C to constant weight to obtain a functional filler, wherein the mass ratio of the pretreated attapulgite, anhydrous DMF and mixed solution b is 1.6:40:25, and the mass ratio of tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF in the mixed solution b is 0.04:0.4:16.

[0037] Preparation Example 8 The functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution with a mass fraction of 24%, stirring for 20 minutes at a control speed of 600 rpm until uniform, heating to 70°C and stirring for 1.5 hours, centrifuging, washing the precipitate with deionized water until the washing solution is neutral, and then drying at 90°C to constant weight to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution with a mass fraction of 28%, stirring for 15 minutes at a control speed of 600 rpm, then adding KH-560, heating to 45°C, stirring for 4.5 hours, centrifuging, washing the precipitate with deionized water 4 times, and drying at 60°C to constant weight to obtain pretreated attapulgite, wherein the mass ratio of attapulgite to the nitric acid solution with a mass fraction of 24% is 2.5:45, and the mass ratio of acidified attapulgite, the ethanol aqueous solution with a mass fraction of 24% and KH-560 is 1.5:24:0.45; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, control the ultrasonic frequency to 35kHz, the ultrasonic power to 550w, and ultrasonicate for 35min, and drip tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF mixed solution b, and control the dripping to be completed within 10min. After the dripping is completed, the temperature is raised to 105°C, the speed is controlled to 700rpm, and the reaction is stirred for 2.5h. After the reaction is completed, centrifuge, and the precipitate is washed 4 times with anhydrous ethanol and deionized water, and then dried at 55°C to constant weight to obtain a functional filler, wherein the mass ratio of the pretreated attapulgite, anhydrous DMF and mixed solution b is 1.8:45:30, and the mass ratio of tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF in the mixed solution b is 0.04:0.5:18.

[0038] Preparation Example 9 The functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution with a mass fraction of 26%, stirring for 30 minutes at a controlled speed of 600 rpm until uniform, heating to 80°C and stirring for 2 hours, centrifuging, washing the precipitate with deionized water until the washing liquid is neutral, and then drying at 80°C to constant weight to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution with a mass fraction of 30%, stirring for 20 minutes, then adding KH-560, heating to 50°C, stirring for 5 hours, centrifuging, and drying the precipitate to obtain pretreated attapulgite, wherein the mass ratio of attapulgite to the nitric acid solution with a mass fraction of 26% is 3:50, and the mass ratio of the acidified attapulgite, the ethanol aqueous solution with a mass fraction of 30% and KH-560 is 2:26:0.3; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, control the ultrasonic frequency to 30kHz, the ultrasonic power to 500w, the ultrasonic treatment for 40min, and drip tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF mixed solution b, and control the dripping to be completed within 10min. After the dripping is completed, the temperature is raised to 110°C, the speed is controlled to 800rpm, and the stirring reaction is continued for 3h. After the reaction is completed, centrifugation is performed, and the precipitate is washed 5 times with anhydrous ethanol and deionized water, and then dried at 60°C to constant weight to obtain a functional filler, wherein the mass ratio of the pretreated attapulgite, anhydrous DMF and mixed solution b is 2.0:50:35, and the mass ratio of tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF in the mixed solution b is 0.04:0.6:20.

[0039] Comparative Preparation Example 7 The functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution with a mass fraction of 22%, stirring for 30 minutes at a control speed of 500 rpm until uniform, heating to 60°C, maintaining the speed unchanged, continuing to stir for 1 hour, centrifuging, washing the precipitate with deionized water until the washing liquid is neutral, and then drying at 80°C to constant weight to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution with a mass fraction of 26%, stirring for 10 minutes at a control speed of 600 rpm, then adding KH-560, heating to 40°C, maintaining the speed unchanged, continuing to stir and react for 4 hours, centrifuging, washing the precipitate with deionized water 3 times, and drying at 55°C to constant weight to obtain pretreated attapulgite, wherein the mass ratio of attapulgite to the nitric acid solution with a mass fraction of 22% is 2:40, and the mass ratio of acidified attapulgite, the ethanol aqueous solution with a mass fraction of 22% and KH-560 is 1:22:0.3; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, control the ultrasonic frequency to 40kHz, the ultrasonic power to 600w, and ultrasonicate for 30min, and drip tetrabutylammonium bromide, glycine and anhydrous DMF mixed solution b, and control the dripping to be completed within 10min. After the dripping is completed, the temperature is raised to 100°C, the speed is controlled to 600rpm, and the reaction is stirred for 2h. After the reaction is completed, centrifuge, and the precipitate is washed with anhydrous ethanol and deionized water for 3 times, and then dried at 50°C to constant weight to obtain a functional filler, wherein the mass ratio of the pretreated attapulgite, anhydrous DMF and mixed solution b is 1.6:40:25, and the mass ratio of tetrabutylammonium bromide, glycine and anhydrous DMF in the mixed solution b is 0.04:0.4:16.

[0040] Examples 1-3 and Comparative Examples 1-4 provide a water-based quick-drying coating for corrosion protection of aluminum alloy substrates and a preparation method thereof.

[0041] Example 1 This embodiment provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28 parts of dicyandiamide, 56 parts of the water-based epoxy prepolymer component prepared in Preparation Example 4, 14 parts of the functional filler prepared in Preparation Example 7, 0.5 parts of Foamex-815, 0.6 parts of BYK-381, 0.8 parts of BYK-346 and 3 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, Foamex-815 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1100 rpm, and the mixture was stirred for 20 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0042] Example 2 This embodiment provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 34 parts of diaminodiphenyl sulfone, 67 parts of the water-based epoxy prepolymer component prepared in Preparation Example 5, 16 parts of the functional filler prepared in Preparation Example 8, 0.9 parts of Foamex-8030, 1.0 parts of BYK-348, 1.1 parts of BYK-190 and 5 parts of K-54; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, diaminodiphenyl sulfone BYK-348, BYK-190, Foamex-8030 and K-54 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1200 rpm, and stirring was performed for 15 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0043] Example 3 This embodiment provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 40 parts of dicyandiamide, 78 parts of the water-based epoxy prepolymer component prepared in Preparation Example 6, 18 parts of the functional filler prepared in Preparation Example 9, 1.3 parts of BYK-024, 1.4 parts of BYK-381, 1.6 parts of BYK-346 and 7 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, BYK-024 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1300 rpm, and stirring was performed for 10 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0044] Comparative Example 1 This comparative example provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28 parts of dicyandiamide, 56 parts of the water-based epoxy prepolymer component prepared in Comparative Preparation Example 4, 14 parts of the functional filler prepared in Preparation Example 7, 0.5 parts of Foamex-815, 0.6 parts of BYK-381, 0.8 parts of BYK-346 and 3 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, Foamex-815 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1100 rpm, and the mixture was stirred for 20 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0045] Comparative Example 2 This comparative example provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28 parts of dicyandiamide, 56 parts of the water-based epoxy prepolymer component prepared in Comparative Preparation Example 5, 14 parts of the functional filler prepared in Preparation Example 7, 0.5 parts of Foamex-815, 0.6 parts of BYK-381, 0.8 parts of BYK-346 and 3 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, Foamex-815 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1100 rpm, and the mixture was stirred for 20 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0046] Comparative Example 3 This comparative example provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28 parts of dicyandiamide, 56 parts of the water-based epoxy prepolymer component prepared in Comparative Preparation Example 6, 14 parts of the functional filler prepared in Preparation Example 7, 0.5 parts of Foamex-815, 0.6 parts of BYK-381, 0.8 parts of BYK-346 and 3 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, Foamex-815 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1100 rpm, and the mixture was stirred for 20 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0047] Comparative Example 4 This comparative example provides a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, comprising the following raw materials in parts by weight: 28 parts of dicyandiamide, 56 parts of the water-based epoxy prepolymer component prepared in Preparation Example 4, 14 parts of the functional filler prepared in Comparative Preparation Example 7, 0.5 parts of Foamex-815, 0.6 parts of BYK-381, 0.8 parts of BYK-346 and 3 parts of DMP-30; The preparation method of the water-based quick-drying coating for anti-corrosion of aluminum alloy substrate comprises the following steps: Functional filler, dicyandiamide, BYK-381, BYK-346, Foamex-815 and DMP-30 were added to the water-based epoxy prepolymer component under stirring, the rotation speed was controlled to 1100 rpm, and the mixture was stirred for 20 minutes until uniform, thereby obtaining a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

[0048] Performance Testing 1. Mechanical properties The water-based quick-drying coatings for anti-corrosion of aluminum alloy substrates prepared in Examples 1-3 and Comparative Examples 1-4 were poured onto a clean polytetrafluoroethylene plate, and coated sequentially from 100 μm, 200 μm, 300 μm to 600 μm using a four-sided film applicator, dried and cured at room temperature for 24 hours, then transferred to an oven, dried at 70° C. for 12 hours, and then cured at 23° C. and 50% humidity for 7 hours, and the film was separated from the polytetrafluoroethylene plate with a scraper to obtain a complete water-based epoxy film, and the mechanical properties of the coating, namely, tensile modulus, tensile strength and elongation at break, were tested using the ASTM D882-12 material testing system; Adhesion test: According to the standard ASTMD 4541, the prepared coating was 2 The amount of the coating was applied on the aluminum alloy plate. The material of the aluminum alloy plate conforms to the standard GB / T 3880.1-2023. After sandblasting, the rust removal level reached Sa2.5 level specified in GB / T8923, and the surface roughness reached the intermediate level specified in GB / T13288.1. After curing for 7 days at 23±2℃ and 50±5% humidity, the test was carried out. Pencil hardness: measured in accordance with the standard of GB / T6739-2006 "Paints and varnishes: Determination of film hardness by pencil method". The specific test results are shown in Table 1. Table 1 Mechanical properties test of water-based quick-drying coating for anti-corrosion of aluminum alloy substrates

[0049] It can be seen from Table 1 that compared with comparative examples 1-4, the coatings prepared in Examples 1-3 have good tensile properties, high adhesion and high hardness. In summary, the water-based quick-drying coatings for corrosion protection of aluminum alloy substrates prepared in Examples 1-3 of the present application have more excellent mechanical properties.

[0050] 2. Weather resistance test The acid resistance, alkali resistance, salt resistance and aging resistance of the water-based quick-drying coatings for anti-corrosion of aluminum alloy substrates prepared in Examples 1-3 and Comparative Examples 1-4 were tested. The specific technical indicators and test methods are shown in Table 2 below, and the specific test results are shown in Table 3 below: Table 2 Corrosion resistance and aging resistance test methods and technical indicators

[0051] Table 3 Weathering performance test of water-based quick-drying coatings for anti-corrosion of aluminum alloy substrates

[0052] It can be seen from Table 3 that compared with Comparative Examples 1-4, the coatings prepared in Examples 5-7 have good aging resistance, and the paint films have not undergone significant changes after being immersed in acid solutions, alkaline solutions and salt solutions for a longer time. At the same time, their surface drying time and actual drying time are both shorter. Therefore, the water-based quick-drying coating for anti-corrosion of aluminum alloy substrates prepared by the present invention has more excellent performance.

[0053] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A water-based quick-drying coating for anti-corrosion of aluminum alloy substrates, characterized in that: The invention comprises the following raw materials in parts by weight: 28-40 parts of waterborne epoxy resin emulsion curing agent, 56-78 parts of waterborne epoxy prepolymer component, 14-18 parts of functional filler, 0.5-1.3 parts of defoamer, 0.6-1.4 parts of leveling agent, 0.8-1.6 parts of wetting dispersant and 3-7 parts of curing accelerator; The waterborne epoxy prepolymer component is prepared by firstly reacting an epoxy prepolymer with ethanolamine through a ring-opening reaction and then dispersing it into deionized water; The epoxy prepolymer is firstly subjected to a ring-opening esterification reaction of trimethylolaminomethane and octadecene succinic anhydride to obtain an unsaturated monomer, which is then subjected to a hydrosilylation reaction with 1,1,3,3-tetramethyldisiloxane to obtain a modifier, which is then subjected to an amidation reaction and a self-condensation reaction with diethylenetriamine to obtain an imidazoline monomer, and finally subjected to an electrophilic substitution reaction with benzyl chloride to obtain the epoxy prepolymer.

2. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 1, characterized in that: The preparation method of the waterborne epoxy prepolymer component comprises the following steps: Add epoxy prepolymer and ethanolamine to anhydrous ethanol, stir evenly, heat to 64-70°C, stir and react for 2-3h, add glacial acetic acid dropwise, and control the dripping to be completed within 10min. After the dripping is completed, continue stirring for 0.3-0.6h, then add deionized water, continue stirring and react for 0.4-0.8h to obtain a water-based epoxy prepolymer component, wherein the usage ratio of epoxy prepolymer, anhydrous ethanol, ethanolamine, glacial acetic acid and deionized water is 2-3:20-30:0.18-0.22:0.06-0.10:

35.

3. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 1, characterized in that: The step A1, tris(hydroxymethyl)aminomethane and anhydrous DMF are mixed evenly, the temperature is raised to 35-45° C., and a mixed solution a of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol is added dropwise while stirring, and the dripping is controlled to be completed within 30 minutes. After the dripping is completed, the temperature is raised to 72-76° C., and the stirring reaction is continued for 4-6 hours. After the reaction is completed, the pH is adjusted to neutral, and the mixture is rotary evaporated, washed, and dried to obtain an unsaturated monomer; Step A2, adding an unsaturated monomer and a platinum catalyst to isopropanol, heating to 30-40° C., stirring evenly, adding 1,1,3,3-tetramethyldisiloxane dropwise while stirring, and controlling the dripping to be completed within 30 minutes. After the dripping is completed, heating to reflux, stirring and reacting for 6-8 hours, cooling to room temperature after the reaction is completed, rotary evaporation, washing, and drying to obtain a modifier; Step A3, under nitrogen protection, add the modifier and diethylenetriamine to xylene, stir evenly at room temperature, then heat to 145-155° C., continue stirring to react for 1.6-2.2 hours, then heat to 195-205° C., continue stirring to react for 2-3 hours to obtain an imidazoline monomer, after the reaction is completed, cool to 90-100° C., add benzyl chloride, heat to reflux to react for 3-4 hours, and rotary evaporate to obtain an anticorrosion enhancement component; Step A4, add the anticorrosion enhancement component to anhydrous DMF, heat to 45-55°C, stir evenly, add epichlorohydrin dropwise, and control the dripping to be completed within 10 minutes. After the dripping is completed, heat to 64-76°C, stir and react for 6-8 hours. After the reaction is completed, filter with suction, wash and dry the filter cake to obtain an epoxy prepolymer.

4. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 3, characterized in that: In the step A1, the mass ratio of tris(hydroxymethyl)aminomethane, anhydrous DMF and mixed solution a is 1-2:30-40:15-25, and in the mixed solution a, the mass ratio of octadecenylsuccinic anhydride, 4-dimethylaminopyridine and isopropanol is 3.2-5.8:0.08-0.12:

20.

5. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 3, characterized in that: In the step A2, the mass ratio of the unsaturated monomer, the platinum catalyst, isopropanol and 1,1,3,3-tetramethyldisiloxane is 5.6-12.2: 1-2: 45-55: 0.8-1.

8.

6. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 3, characterized in that: In the step A3, the mass ratio of the modifier, diethylenetriamine, xylene and benzyl chloride is 5-10: 0.4-0.8: 36-42: 0.6-1.

1.

7. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 3, characterized in that: In the step A4, the mass ratio of the anti-corrosion enhancing component, anhydrous DMF and epichlorohydrin is 5.4-8.2:30-40:0.72-0.

98.

8. The water-based quick-drying paint for anti-corrosion of aluminum alloy substrates according to claim 1, characterized in that: The functional filler is prepared by the following steps: Step B1, adding attapulgite to a nitric acid solution, stirring evenly, heating to 60-80°C, continuing stirring for 1-2h, centrifuging, washing and drying the precipitate to obtain acidified attapulgite, adding the acidified attapulgite to an ethanol aqueous solution, stirring for 10-20min, then adding KH-560, heating to 40-50°C, stirring for 4-5h, centrifuging, washing and drying the precipitate to obtain pretreated attapulgite; Step B2, ultrasonically disperse the pretreated attapulgite in anhydrous DMF, drop tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF mixed solution b, and control the dropwise addition within 10 minutes. After the dropwise addition is completed, the temperature is raised to 100-110° C., and the reaction is stirred for 2-3 hours. After the reaction is completed, centrifuge, wash the precipitate, and dry it to obtain a functional filler.

9. The water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to claim 8, characterized in that: In the step B1, the mass ratio of attapulgite and nitric acid solution is 2-3:40-50, the mass fraction of nitric acid solution is 22-26%, the mass ratio of acidified attapulgite, ethanol aqueous solution and KH-560 is 1-2:22-26:0.3-0.6, and the mass fraction of ethanol aqueous solution is 26-30%. In the step B2, the mass ratio of pretreated attapulgite, anhydrous DMF and mixed solution b is 1.6-2.0:40-50:25-35, and in the mixed solution b, the mass ratio of tetrabutylammonium bromide, 6-aminopyridine-2-carboxylic acid and anhydrous DMF is 0.04:0.4-0.6:16-20.

10. A method for preparing a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates according to any one of claims 1 to 9, characterized in that: The following steps are involved: Functional fillers, water-based epoxy resin emulsion curing agent, leveling agent, wetting dispersant, defoaming agent and curing accelerator are added to the water-based epoxy prepolymer component under stirring, and the mixture is stirred evenly to obtain a water-based quick-drying coating for anti-corrosion of aluminum alloy substrates.

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