Corrosion-resistant waterborne acrylic polyurethane coating as well as preparation method and application thereof

Abstract

The invention discloses a corrosion-resistant waterborne acrylic polyurethane coating and a preparation method and application thereof, and relates to the field of resin paints.The corrosion-resistant waterborne acrylic polyurethane coating is composed of a component A and a component B. The component A comprises waterborne hydroxyl acrylic resin, corrosion-resistant composite filler, a polyurethane rheological additive and deionized water, and the component B comprises an isocyanate curing agent and a diluent; the preparation method comprises the following steps: S1, adding the polyurethane associated rheological additive into the water-based hydroxy acrylic resin, uniformly stirring and mixing, adding the deionized water and the corrosion-resistant composite filler, and uniformly stirring and mixing to obtain a component A; s2, uniformly stirring a diluent and an isocyanate curing agent to obtain a component B; and S3, uniformly mixing the component A and the component B according to a ratio. According to the final product, the corrosion resistance of the surface coating can be improved, and the adverse effect of seawater corrosion on the bonding strength of the coating on the surface of the container is reduced.

Description

Technical Field

[0001] This application relates to the field of resin coatings, and in particular to a corrosion-resistant waterborne acrylic polyurethane coating, its preparation method, and its uses. Background Technology

[0002] With global climate change and increasingly scarce fossil resources, countries around the world are encouraging the promotion and use of energy-saving and environmentally friendly products. Water-based coatings contain little or no volatile organic compounds and are free of harmful air pollutants, thus contributing to the rational use of resources, environmental protection, and human health, and have become a new direction for coating technology development.

[0003] Waterborne acrylic polyurethane coatings are a two-component system consisting of a crosslinking curing agent containing -NCO groups (component B) and an acrylic emulsion containing hydroxyl groups (component A). Through the reaction of active groups, a three-dimensional network crosslinked structure is formed during the film-forming process. It has properties such as low film-forming temperature, high gloss, strong adhesion, high hardness, and good chemical resistance and weather resistance. It is a decorative coating that can be widely used in industrial corrosion protection.

[0004] Container shipping by sea is the most important mode of transportation for international trade goods. During sea voyages, the surface coating is easily corroded by seawater, which reduces the coating's adhesion to the container surface and prevents it from providing effective protection. Summary of the Invention

[0005] In order to improve the corrosion resistance of the surface coating and reduce the adverse effects of seawater erosion on the bonding strength of the coating on the container surface, this application provides a corrosion-resistant waterborne acrylic polyurethane coating, its preparation method and application.

[0006] Firstly, this application provides a corrosion-resistant waterborne acrylic polyurethane coating. The following technical solution is adopted: It is composed of component A and component B. Component A includes 30 to 100 parts of waterborne hydroxyl acrylic resin, 10 to 30 parts of corrosion-resistant composite filler, 0.5 to 2.5 parts of polyurethane rheology modifier, and 1 to 10 parts of deionized water. Component B includes 65 to 85 parts of isocyanate curing agent and 15 to 25 parts of diluent.

[0007] By adopting the above technical solutions, water is used as the dispersion medium, significantly reducing organic solvents and VOCs. Low-toxicity isocyanate curing agents are used to avoid the toxicity problems of traditional solvent-based coatings. Hydroxy acrylic resin provides a rigid skeleton, and isocyanate cross-linking forms a dense network, improving the coating hardness. The cross-linked structure resists corrosion from oil, solvents, acid rain, etc. The combination of the flexibility of acrylic resin and the toughness of polyurethane makes the coating less prone to cracking. The addition of corrosion-resistant composite fillers also effectively improves the coating's resistance to chloride ion erosion and reduces the adverse effects of seawater erosion on the coating's bonding strength on the container surface.

[0008] Preferably, the weight ratio of component A to component B is 1 to 5:1.

[0009] By adopting the above technical solution, after the A component and B component are mixed, high performance is achieved through cross-linking reaction. The cross-linked coating has higher mechanical strength, chemical resistance and durability, far exceeding that of single-component physical drying coatings. It significantly improves coating durability, enhances environmental adaptability, optimizes construction flexibility and extends service life.

[0010] Preferably, component A further includes 2-5 parts of dispersant, 0.1-0.5 parts of catalyst, 0.1-1 parts of substrate wetting agent, and 0.1-1 parts of silicone defoamer.

[0011] By employing the above technical solutions, dispersants can improve leveling properties, reduce coating viscosity, facilitate spraying or brushing, reduce defects such as sagging and orange peel, enhance gloss and hiding power, form a denser paint film, and improve surface gloss and hiding efficiency; catalysts can accelerate the reaction between isocyanates and hydroxyl groups, significantly improving curing efficiency and optimizing material properties; substrate wetting agents improve the wetting and adhesion of coatings to substrates. They help liquids spread better on the substrate surface by reducing surface tension; and silicone defoamers can quickly eliminate foam and inhibit foam regeneration, thereby improving production efficiency and product quality.

[0012] Preferably, component B further includes 1 to 5 parts of a dehydrating agent.

[0013] By adopting the above technical solution, the dehydrating agent can adsorb or react to remove trace amounts of moisture in the system, preventing moisture from affecting product performance or causing poor curing.

[0014] Preferably, the corrosion-resistant composite filler is a basalt flake modified chloride ion binder.

[0015] By adopting the above technical solution, basalt flakes are used as the outermost protective layer to resist chloride ion erosion. Chloride ions that continue to seep in through the gaps in the basalt flakes are bound and cannot penetrate further, effectively reducing the damage of chloride ion erosion to the coating and substrate.

[0016] Preferably, the corrosion-resistant composite filler is prepared by the following steps: S1, methanol and deionized water are mixed in proportion, cordierite honeycomb ceramic powder is added and stirred until uniform, chloride ion scavenger is added and stirred until uniform, and then the mixture is allowed to stand for 6 hours. S2. Continue to add basalt flakes and stir for 24 hours. After centrifugation, wash with deionized water several times and dry with hot air to obtain basalt flake modified chloride ion binder.

[0017] By adopting the above technical solution, cordierite honeycomb ceramic powder is first used as the carrier of chloride ion scavenger to form internal particles that can absorb and solidify chloride ions. Then, basalt flakes are used as the outer layer of protection. The three-layer structure effectively reduces chloride ion erosion.

[0018] Preferably, the chloride ion scavenger is N,N'-bis(3-trimethoxysilylpropyl)thiourea.

[0019] By adopting the above technical solution, the long-chain structure of N,N'-bis(3-trimethoxysilylpropyl)thiourea is fixed on cordierite ceramic powder particles on the one hand, and combined with basalt flakes on the other hand. The basalt flakes seal the pores on the surface of cordierite ceramic powder particles, reducing the pores' ability to introduce chloride ions.

[0020] Part Two: This application provides a method for preparing a corrosion-resistant waterborne acrylic polyurethane coating, comprising the following steps: S1, adding a polyurethane rheology modifier to a waterborne hydroxy acrylic resin, stirring and mixing evenly, then adding deionized water and a corrosion-resistant composite filler and stirring and mixing evenly to obtain component A; S2, stirring a diluent and an isocyanate curing agent evenly to obtain component B; S3, mixing component A and component B evenly in a certain proportion to obtain the corrosion-resistant waterborne acrylic polyurethane coating.

[0021] By adopting the above technical solutions, the products are safe and environmentally friendly, low in VOCs, efficient in construction, rheologically adjustable, adaptable to various coating methods, fast curing speed, stable and controllable, with good storage stability, moderate activation period, and easy for large-scale production.

[0022] Part Three, this application provides an application of a corrosion-resistant waterborne acrylic polyurethane coating for use as an anti-corrosion surface coating in industries such as automobiles, electronics, and containers.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. Cordierite honeycomb ceramic powder is used as a carrier for chloride ion scavenging to form internal particles that can absorb and solidify chloride ions. Then, basalt flakes are used as an outer protective layer. The three-layer structure effectively reduces chloride ion erosion. 2. By utilizing the long-chain structure of N,N'-bis(3-trimethoxysilylpropyl)thiourea, the particles of cordierite ceramic powder are fixed on one hand, and combined with basalt flakes on the other hand. The basalt flakes seal the pores on the surface of the cordierite ceramic powder particles, reducing the introduction of chloride ions by the pores. 3. By combining water-based hydroxyl acrylic resin, polyurethane rheology modifier, and isocyanate curing agent, a balance between environmental protection and high performance is achieved. It is especially suitable for fields with stringent requirements for durability and appearance. Its comprehensive performance far exceeds that of single-component water-based coatings, making it an ideal choice to replace solvent-based products. Detailed Implementation

[0024] The present application will be further described in detail below with reference to the embodiments.

[0025] In this application, the waterborne hydroxyl acrylic resin is designated MACRYNAL®SM 6817w / 44WA; the polyurethane rheology modifier is THIXATROL PLUS; the dispersant is BYK-191 (Germany); the catalyst is Borchers LH 10; the substrate wetting agent is Efka FL 3772; the silicone defoamer is BYK-024; the isocyanate curing agent is Bayhydur XP 2655; the diluent is propylene glycol methyl ether; and the dehydrating agent is SN-9088.

[0026] Preparation Example 1 This preparation example provides a corrosion-resistant composite filler, which is prepared by the following steps: S1. Mix 25 mL of methanol with 75 mL of deionized water, add 5 g of cordierite honeycomb ceramic powder (particle size D50 = 0.5 μm) and stir until well mixed. Then add 10 g of N,N'-bis(3-trimethoxysilylpropyl)thiourea and stir until well mixed. Let stand for 6 h. S2. Continue to add 5g of basalt flakes (crushed to 1000 mesh) and stir for 24 hours. After centrifugation, wash with deionized water 3 times and dry with hot air at 90℃ to obtain basalt flake modified chloride ion binder, i.e. corrosion resistant composite filler. The long-chain structure of N,N'-bis(3-trimethoxysilylpropyl)thiourea is used to fix cordierite ceramic powder particles on one hand, and to combine with basalt flakes on the other hand. The basalt flakes seal the pores on the surface of cordierite ceramic powder particles, reducing the pores' ability to introduce chloride ions.

[0027] Preparation Example 2 This preparation example provides a corrosion-resistant composite filler, which is prepared by the following steps: S1. Mix 25 mL of methanol with 75 mL of deionized water, add 5 g of cordierite honeycomb ceramic powder (particle size D50 = 0.5 μm), stir and mix evenly, and let stand for 6 h. S2. Continue to add 5g of basalt flakes (crushed to 1000 mesh) and stir for 24 hours. After centrifugation, wash with deionized water 3 times and dry with hot air at 90℃ to obtain corrosion-resistant composite filler.

[0028] Preparation Example 3 This preparation example provides a corrosion-resistant composite filler, which is prepared by the following steps: S1. Mix 25 mL of methanol with 75 mL of deionized water, add 5 g of cordierite honeycomb ceramic powder (particle size D50 = 0.5 μm) and stir until well mixed. Then add 10 g of N,N'-bis(3-trimethoxysilylpropyl)thiourea and stir until well mixed. Let stand for 6 h. S2. After centrifugation, wash three times with deionized water and dry with hot air at 90℃ to obtain corrosion-resistant composite packing.

[0029] Preparation Example 4 S1. Mix 25 mL of methanol with 75 mL of deionized water, add 10 g of N,N'-bis(3-trimethoxysilylpropyl)thiourea, stir and mix evenly, and let stand for 6 h. S2. Continue to add 5g of basalt flakes (crushed to 1000 mesh) and stir for 24 hours. After centrifugation, wash with deionized water 3 times and dry with hot air at 90℃ to obtain corrosion-resistant composite filler.

[0030] Cordierite honeycomb ceramic powder is used as a carrier for chloride ion scavenging to form internal particles that can absorb and solidify chloride ions. Then, basalt flakes are used as an outer protective layer. The three-layer structure effectively reduces chloride ion erosion.

[0031] Example 1 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 0.5 kg of polyurethane rheology modifier, 2 kg of dispersant, 0.1 kg of catalyst, 0.1 kg of substrate wetting agent, and 0.1 kg of organosilicon defoamer to 30 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 1 kg of deionized water and 10 kg of corrosion-resistant composite filler prepared in Example 1 and stir and mix evenly to obtain component A. S2. Mix 1 kg of dehydrating agent, 15 kg of diluent and 65 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 1:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0032] Example 2 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 1 and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0033] Example 3 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 2.5 kg of polyurethane rheology modifier, 5 kg of dispersant, 0.5 kg of catalyst, 1 kg of substrate wetting agent, and 1 kg of organosilicon defoamer to 100 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 10 kg of deionized water and 30 kg of corrosion-resistant composite filler prepared in Example 1. Stir and mix evenly to obtain component A. S2. Mix 5 kg of dehydrating agent, 25 kg of diluent and 85 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B evenly in a 5:1 ratio to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0034] Example 4 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier to 65 kg of waterborne hydroxy acrylic resin and stir until uniformly mixed. Then add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 1 and stir until uniformly mixed to obtain component A. S2. Mix 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0035] Example 5 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 1 and stir and mix evenly to obtain component A. S2. Mix 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0036] Example 6 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier to 65 kg of waterborne hydroxy acrylic resin, stir and mix evenly, then add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 1, stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0037] Example 7 This embodiment discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 1 and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B evenly in a 7:1 ratio to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0038] Comparative Example 1 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 2. Stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0039] Comparative Example 2 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 3 and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0040] Comparative Example 3 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of organosilicon defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of corrosion-resistant composite filler prepared in Example 4 and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0041] Comparative Example 4 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5kg of polyurethane rheology modifier, 3kg of dispersant, 0.3kg of catalyst, 0.5kg of substrate wetting agent, and 0.5kg of silicone defoamer to 65kg of waterborne hydroxyl acrylic resin. After stirring and mixing evenly, add 5kg of deionized water and 20kg of cordierite honeycomb ceramic powder and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0042] Comparative Example 5 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5kg of polyurethane rheology modifier, 3kg of dispersant, 0.3kg of catalyst, 0.5kg of substrate wetting agent, and 0.5kg of organosilicon defoamer to 65kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5kg of deionized water and 20kg of basalt flakes and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0043] Comparative Example 6 This comparative example discloses a corrosion-resistant waterborne acrylic polyurethane coating, which is prepared by the following steps: S1. Add 1.5 kg of polyurethane rheology modifier, 3 kg of dispersant, 0.3 kg of catalyst, 0.5 kg of substrate wetting agent, and 0.5 kg of silicone defoamer to 65 kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5 kg of deionized water and 20 kg of N,N'-bis(3-trimethoxysilylpropyl)thiourea and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0044] Comparative Example 7 S1. Add 1.5kg of polyurethane rheology modifier, 3kg of dispersant, 0.3kg of catalyst, 0.5kg of substrate wetting agent, and 0.5kg of silicone defoamer to 65kg of waterborne hydroxy acrylic resin. After stirring and mixing evenly, add 5kg of deionized water and stir and mix evenly to obtain component A. S2. Mix 3 kg of dehydrating agent, 20 kg of diluent and 75 kg of isocyanate curing agent evenly to obtain component B; S3. Mix component A and component B in a 3:1 ratio until homogeneous to obtain a corrosion-resistant waterborne acrylic polyurethane coating.

[0045] Performance testing and analysis The impact resistance of the examples and comparative examples was tested according to GB / T 1732-93 "Test Method for Impact Resistance of Coating Film".

[0046] According to GB / T 9274-88 "Determination of resistance to liquid media for paints and varnishes", Method A was used to test the examples and comparative examples. The liquid used was a 30% sodium chloride aqueous solution.

[0047] Performance testing and analysis The impact resistance of the examples and comparative examples was tested (kg·cm) according to GB / T 1732-93 "Test Method for Impact Resistance of Coating Film". The specific data are shown in Table 1.

[0048] According to GB / T 9274-1988 "Determination of resistance to liquid media for paints and varnishes", test method A was used to test the salt water resistance (h) of the examples and comparative examples. The liquid used was a 30% sodium chloride aqueous solution. The specific data are shown in Table 1.

[0049] According to GB / T1865-2009 "Artificial Climate Aging and Artificial Radiation Exposure to Filtered Xenon Arc Radiation", the examples were subjected to artificial climate aging (h). After 500h, no blistering, peeling, or cracking was observed. Specific data are shown in Table 1.

[0050] According to GB / T9274-1988 "Determination of resistance to liquid media for paints and varnishes", the acid resistance of the examples was tested, with no abnormalities observed after 24 hours of 50 g / L sulfuric acid; and the alkali resistance was tested, with no abnormalities observed after 24 hours of 50 g / L sodium hydroxide. The details are shown in Table 2.

[0051] The water resistance performance of the examples was tested according to GB / T 1733-1993 "Determination of Water Resistance of Coating Film". No abnormalities were found after 48 hours. The details are shown in Table 2.

[0052] Table 1 Performance test data for examples and comparative examples

[0053] Table 2 Performance Test Table of Examples

[0054] Referring to Example 2 and Comparative Examples 1-7 and in conjunction with Table 1, it can be seen that the long-chain structure of N,N'-bis(3-trimethoxysilylpropyl)thiourea achieves both fixation on cordierite ceramic powder particles and bonding with basalt flakes. The basalt flakes seal the pores on the surface of the cordierite ceramic powder particles, reducing the introduction of chloride ions through the pores. Using cordierite honeycomb ceramic powder as a carrier for chloride ion scavenging, internal particles that can absorb and solidify chloride ions are formed. Then, basalt flakes serve as an outer protective layer. Through this three-layer structure, chloride ion erosion is effectively reduced.

[0055] Referring to Examples 2 and 5 and in conjunction with Table 1, it can be seen that by adding various additives and mixing with water-based acrylic resin to prepare component A, the dispersion performance of each component can be effectively improved, thereby indirectly improving the coating performance.

[0056] Referring to Examples 2 and 6 and in conjunction with Table 1, it can be seen that removing trace amounts of moisture with a dehydrating agent reduces bubble formation and effectively improves the overall stability of the coating.

[0057] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A corrosion-resistant waterborne acrylic polyurethane coating, characterized in that: It is composed of component A and component B, wherein the weight ratio of component A to component B is 1 to 5:

1. Component A includes 30 to 100 parts of waterborne hydroxyl acrylic resin, 10 to 30 parts of corrosion-resistant composite filler, 0.5 to 2.5 parts of polyurethane rheology modifier, and 1 to 10 parts of deionized water. Component B includes 65 to 85 parts of isocyanate curing agent and 15 to 25 parts of diluent. The corrosion-resistant composite filler is a basalt flake modified chloride ion binder; The corrosion-resistant composite filler is prepared by the following steps: S1, Methanol and deionized water are mixed at a volume ratio of 1:3, cordierite honeycomb ceramic powder is added and stirred until uniform, chloride ion scavenger is added and stirred until uniform, and then left to stand for 6 hours. S2. Continue to add basalt flakes and stir for 24 hours. After centrifugation, wash with deionized water several times and dry with hot air to obtain basalt flake modified chloride ion binder. The chloride ion scavenger is N,N'-bis(3-trimethoxysilylpropyl)thiourea.

2. The corrosion-resistant waterborne acrylic polyurethane coating according to claim 1, characterized in that: Component A further includes 2-5 parts of dispersant, 0.1-0.5 parts of catalyst, 0.1-1 parts of substrate wetting agent, and 0.1-1 parts of silicone defoamer.

3. The corrosion-resistant waterborne acrylic polyurethane coating according to claim 2, characterized in that: Component B also includes 1 to 5 parts of a dehydrating agent.

4. The method for preparing a corrosion-resistant waterborne acrylic polyurethane coating according to claim 1, characterized in that: The process includes the following steps: S1, adding polyurethane rheology modifier to waterborne hydroxy acrylic resin, stirring and mixing evenly, then adding deionized water and corrosion-resistant composite filler and stirring and mixing evenly to obtain component A; S2, stirring the diluent and isocyanate curing agent evenly to obtain component B; S3, mixing component A and component B evenly according to the ratio to obtain corrosion-resistant waterborne acrylic polyurethane coating.

5. The use of the corrosion-resistant waterborne acrylic polyurethane coating according to any one of claims 1-3, characterized in that: Used for anti-corrosion surface coatings in the automotive, electronics, or container industries.

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