High-performance coating and color steel plate prepared from high-performance coating

Abstract

The invention belongs to the technical field of coatings, and particularly relates to a high-performance coating and a color steel plate prepared from the high-performance coating. The coating is prepared from the following components in parts by weight: 120 to 150 parts of waterborne polyurethane dispersion liquid, 5 to 15 parts of long-chain fluorine-containing silane coupling agent modified graphene, 10 to 15 parts of long-chain fluorine-containing silane coupling agent modified carbon nanotubes, 1 to 4 parts of long-chain fluorine-containing silane coupling agent modified hollow glass microspheres, 1 to 8 parts of auxiliaries and 50 to 100 parts of solvent. Two-dimensional sheet-shaped modified graphene, one-dimensional linear modified carbon nanotubes and zero-dimensional modified hollow glass microspheres are added into waterborne polyurethane to construct a three-dimensional space structure. A micro-nano structure is constructed on the surface of the coating in a manner of compounding point, line and surface fillers, so that the hydrophobicity of the coating is improved. The hollow glass microspheres have relatively low density, so that dispersion of the components can be promoted, and a three-dimensional micro-nano coarse structure can be constructed favorably, so that the coating achieves super-hydrophobic performance.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a high-performance coating and a color steel plate prepared therefrom. Background Art

[0002] Inspired by the "lotus effect", people have found that super-hydrophobic surfaces have good self-cleaning, oil-water separation, anti-icing fog and other properties. Therefore, super-hydrophobic materials have attracted much attention in recent years. At present, the most common way to construct super-hydrophobic surfaces is to use super-hydrophobic coatings. The main preparation method of super-hydrophobic coatings is the sol-gel method, which generates nanoparticles with a certain chain length and particle size through self-hydrolysis and condensation reactions, and then uses low-surface energy substances to modify the nanoparticles. The characteristics of this preparation method are that the synthesis process of the nanoparticles is controllable, the degree of modification is controllable, and the raw materials are extensive. The prepared coating is applied to the surface of the material by dipping, spraying, etc. Once the preparation process parameters of the super-hydrophobic coating are determined, the quality of its performance directly depends on the coating process. The commonly used coating process at this stage is spraying. Its advantage is that the rough structure obtained is large, so the hydrophobic effect is good; the disadvantage is that the construction operation is difficult and requires a lot of equipment. During the spraying process, there are certain requirements for parameters such as the air pressure, gas flow rate, and atomization level of the spray gun, which can easily cause uneven spraying. And because the coating surface obtained by spraying is rougher than that of dip coating, the transparency of the material is poor.Compared to spraying, dip coating is more possessed of operability and practicality.Because the coating of dip coating can be more uniform, and for the positions such as complex devices, cavity interior and slits, dip coating is the only feasible method.In addition, the method for preparing super-hydrophobic coating also has etching method, electrostatic spinning method, electrodeposition method, hydrothermal method etc., but many of them have complex preparation methods, and manufacturing cost is large, and the coating wear resistance of preparation is poor, and low bonding fastness with substrate has limited its range of application.

[0003] Currently, research on superhydrophobic surfaces, both domestically and internationally, primarily focuses on the use of volatile organic compounds as solvents to create these surfaces. However, relatively few technologies have been developed for developing green, environmentally friendly, water-based superhydrophobic coatings using water as a solvent. This is primarily due to the fact that the hydrophilic groups remaining within and on the surface of the coating after water evaporation can affect the hydrophobic stability and durability of the coating, limiting its practical application.

[0004] Waterborne polyurethane is a rapidly developing water-based polymer material with advantages such as non-toxicity, environmental friendliness, and safety, making it an ideal raw material for the production of environmentally friendly products. Patents CN119752303A and CN119684886A, filed by our company's technical partner, Zibo Jiayue Board Industry Co., Ltd., demonstrate the use of graphene and granular inorganic nanofillers to produce waterborne polyurethane coatings with high adhesion and corrosion resistance. However, these coatings exhibit a high degree of hydrophilicity and lack super-hydrophobicity. The company subsequently sought to improve the coating's hydrophobicity by preparing silicone-polyurethane composites. However, this preparation process requires the use of large amounts of organic solvents, which not only creates significant pollution but also provides limited improvement in hydrophobicity.

[0005] At present, the technology for preparing hydrophobic waterborne polyurethane coatings through chemical modification is quite mature, but there is little research on its application in the preparation of superhydrophobic coatings. It mainly focuses on the use of silicone or fluorine-containing monomers to prepare silicon- or fluorine-containing polyurethanes. The process is complex, the cost is high, and the scope of industrial application is narrow. Summary of the Invention

[0006] The present invention aims to overcome the problems of high preparation cost, complicated preparation process and difficulty in industrial scale-up of super-hydrophobic materials in the prior art, and proposes a water-based polyurethane composite coating with super-hydrophobic properties and a preparation method thereof, with the aim of preparing a super-hydrophobic composite material with good corrosion resistance using a relatively simple process.

[0007] In order to achieve the above object, the present invention provides a high performance coating comprising the following components in parts by weight: 120-150 parts of aqueous polyurethane dispersion, 5-15 parts of long-chain fluorinated silane coupling agent-modified graphene, 10-15 parts of long-chain fluorinated silane coupling agent-modified carbon nanotubes, 1-4 parts of long-chain fluorinated silane coupling agent-modified hollow glass microspheres, 1-8 parts of auxiliary agent, and 50-100 parts of solvent.

[0008] There are mainly two ways of thinking in preparing super-hydrophobic surfaces, one is to manufacture rough structures on the surface of low surface energy materials; the other is to modify rough surfaces using low surface energy materials. In the traditional method of constructing super-hydrophobic surfaces, single nanoparticles are usually used to construct micro-nano rough structures. In use, the single nanoparticle surface roughness performance of the coating surface is limited, and it is easily subject to mechanical wear and tear and falls off, directly making the coating lose super-hydrophobic characteristics, which has caused a great obstacle to the application of super-hydrophobic coatings. Improving the microstructure of the coating surface can effectively increase the durability of the super-hydrophobic surface. For this reason, the present invention adds two-dimensional flaky graphene modified by long carbon chain fluorine-containing silane coupling agent, one-dimensional linear carbon nanotube modified by long carbon chain fluorine-containing silane coupling agent and zero-dimensional granular hollow glass microsphere modified by long carbon chain fluorine-containing silane coupling agent to waterborne polyurethane to build a three-dimensional space structure. Micro-nano structure is successfully constructed on the coating surface by the method of three kinds of fillers compounded by point, line and surface. Furthermore, nanoscale wrinkles spontaneously form within the graphene space. After the coating dries, they, along with the fibrous carbon nanotubes and micron-sized particles, form a micro-nano raised structure similar to that on a lotus leaf, increasing the overall surface roughness of the composite coating. Furthermore, pores appear between the fibers and particles on the coating surface, allowing air to enter these pores, forming an air layer and further enhancing the hydrophobic properties. These micro-nano structures act as super-hydrophobic agents, while the micron-structures also provide protection against damage to the nanostructure, thus imparting excellent stability to the coating.

[0009] Wherein, the introduction of long carbon chain fluorine-containing silane coupling agent not only reduces the surface energy of Graphene, carbon nanotube and hollow glass microsphere, and long chain structure is mutually intertwined and helps to interconnect between Graphene, carbon nanotube, hollow glass microsphere three, avoids single material to reunite, improves its dispersion property, is conducive to improving the corrosion resistance of coating. Why the present invention selects hollow glass microsphere, is because it has lower density, has better suspension characteristic in aqueous polyurethane coating, can promote the dispersion of Graphene and carbon nanotube, makes zero-dimensional particle, one-dimensional carbon nanotube and two-dimensional Graphene build three-dimensional micro-nano rough structure on coating surface.This structure is very similar to the structure on lotus leaf surface, so coating has lotus effect, can reach the effect of self-cleaning.When coating is exposed in the air, these coarse structures are filled by a large amount of air, form air film, can stop the direct contact with liquid, form the pattern that solid-air-water contacts, thereby makes coating realize super-hydrophobicity.

[0010] In one embodiment, the aqueous polyurethane dispersion has a solid content of 40-80%.

[0011] In one embodiment, the long-chain fluorine-containing silane coupling agent-modified graphene, long-chain fluorine-containing silane coupling agent-modified carbon nanotubes, and long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres are graphene, carbon nanotubes, and hollow glass microspheres modified with a perfluorosilane coupling agent.

[0012] In one embodiment, the long-chain fluorine-containing silane coupling agent is one or more of perfluorodecyltrichlorosilane, perfluorodecyltrimethoxysilane, perfluorodecyltriethoxysilane, perfluorooctyltriethoxysilane, perfluorooctyltrimethoxysilane, and perfluorooctyltrichlorosilane.

[0013] In one embodiment, the graphene has a lateral dimension of 1-10 μm. In particular, the amount of graphene used is 5-10 parts. Graphene, as a common nanoscale filler, has a large aspect ratio. By using linear carbon nanotubes as the main body of the nanostructure, and using lamellar graphene and spherical control particles to construct a micro-nano rough structure on the coating surface. An appropriate amount of graphene not only promotes the formation of micro-nano structures, but also prevents excessive lamellar graphene from affecting the surface morphology of the coating.

[0014] In one embodiment, the carbon nanotubes are 10-50 μm in length. There is no particular limitation on the diameter of the carbon nanotubes, but a typical diameter is 10-80 nm.

[0015] In one embodiment, the hollow glass microspheres have a particle size of 2-50 μm. Compared to incubation glass microspheres, the density of hollow glass microspheres is lower, generally 0.20-0.60 g / cm 3 , has good dispersibility in waterborne polyurethane coatings, can promote the dispersion of two-dimensional graphene and one-dimensional carbon nanotubes. The inventors found that if solid glass microspheres are used, their density is relatively large, and due to sedimentation, they cannot promote the dispersion of graphene and carbon nanotubes, and cannot build a three-dimensional micro-nano rough structure on the coating surface. Its contact angle can only reach about 123 °, which cannot meet the performance requirements of super-hydrophobicity. An appropriate amount of hollow glass microspheres can promote the dispersion of fillers, but when its consumption exceeds a certain range, the increase of excessive inert fillers will increase the instability of the coating, which is unfavorable for the formation of micro-nano structures on the coating surface, resulting in a decrease in contact angle and a decrease in hydrophobicity.

[0016] In one embodiment, the auxiliary agent is one or more of an anti-settling agent, a defoaming agent, a wetting and dispersing agent, a leveling agent, a preservative, and an antibacterial agent.

[0017] In particular, the anti-settling agent is any one of fumed silica, organic bentonite, polyamide wax or polyethylene wax, and modified urea. The defoamer is any one of fluorosilicone-modified polysiloxane defoamers and polydimethylsiloxane defoamers. The wetting and dispersing agent is any one of unsaturated polycarboxylic acid polymers, sodium polyacrylate, triethylhexyl phosphoric acid, sodium lauryl sulfate, methylpentanol, polyacrylamide, gur gum, or fatty acid polyethylene glycol esters. The leveling agent is any one of acrylic acid or fluorophosphate esters. The preservative is any one of LF-B20 preservative, an isothiazolone derivative, or n-octylisothiazolinone.

[0018] In one embodiment, the solvent is deionized water.

[0019] In one embodiment, the preparation process of the long-chain fluorine-containing silane coupling agent modified graphene is: A long-chain fluorine-containing silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, acid is added to adjust the pH, and hydrolysis is performed at room temperature to obtain a mixed solution; graphene is added to the mixed solution, stirred for reaction, and then filtered, washed, and dried to obtain long-chain fluorine-containing silane coupling agent-modified graphene.

[0020] In one embodiment, the mass ratio of the long-chain fluorine-containing silane coupling agent to graphene is (0.05-0.4):1. Specifically, it can be 0.05:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1. Further, it can be 0.1:1 or 0.2:1.

[0021] In one embodiment, the preparation process of the long-chain fluorine-containing silane coupling agent modified carbon nanotubes is: The long-chain fluorine-containing silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, acid is added to adjust the pH, and hydrolysis is performed at room temperature to obtain a mixed solution; carbon nanotubes are added to the mixed solution, stirred for reaction, and then filtered, washed, and dried to obtain long-chain fluorine-containing silane coupling agent-modified carbon nanotubes.

[0022] In one embodiment, the mass ratio of the long-chain fluorine-containing silane coupling agent to the carbon nanotubes is (0.05-0.4):1. Specifically, it can be 0.05:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1. Further, it can be 0.1:1 or 0.2:1.

[0023] In one embodiment, the preparation process of the hollow glass microspheres modified with the long-chain fluorine-containing silane coupling agent is as follows: The long-chain fluorine-containing silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, acid is added to adjust the pH, and hydrolysis is performed at room temperature to obtain a mixed solution; hollow glass microspheres are added to the mixed solution, stirred for reaction, and then filtered, washed, and dried to obtain long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres.

[0024] In one embodiment, the mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres is (0.05-0.4):1. Specifically, it can be 0.05:1, 0.1:1, 0.2:1, 0.3:1, or 0.4:1. Furthermore, it can be 0.1:1 or 0.2:1. Using too little long-chain fluorinated silane coupling agent can lead to incomplete modification of the hollow glass microspheres. However, using too much long-chain fluorinated silane coupling agent can lead to self-crosslinking after hydrolysis, resulting in poor dispersibility of the hollow glass microspheres.

[0025] In one embodiment, the acid is one or more of formic acid, acetic acid, citric acid, and lactic acid, and the pH is 3-5.

[0026] In one embodiment, the hydrolysis time is 1-2 hours, the stirring reaction temperature is 45-55° C., and the reaction time is 4-8 hours.

[0027] In one embodiment, the method for preparing the high performance coating comprises the following steps: In one embodiment, long-chain fluorine-containing silane coupling agent-modified graphene, long-chain fluorine-containing silane coupling agent-modified carbon nanotubes, long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres, and a solvent are uniformly mixed, and then an aqueous polyurethane dispersion is added and stirred and dispersed. Then, an additive is added and mixed again to obtain a high-performance coating.

[0028] In another aspect, the present invention also provides a color-coated steel plate, which is produced by applying a high-performance coating to the surface of a cleaned color-coated steel plate. Applying the high-performance coating to the surface of the color-coated steel plate enhances its hydrophobicity and corrosion resistance, making it suitable for wide application in high-humidity and high-corrosion environments.

[0029] Beneficial effects: Two-dimensional flaky graphene modified with a long carbon chain fluorinated silane coupling agent, one-dimensional linear carbon nanotubes modified with a long carbon chain fluorinated silane coupling agent, and zero-dimensional granular hollow glass microspheres modified with a long carbon chain fluorinated silane coupling agent are added to water-based polyurethane to construct a three-dimensional spatial structure. By compounding the three fillers in the form of points, lines, and surfaces, a micro-nanostructure is successfully constructed on the coating surface, further improving the hydrophobicity of the coating. Among them, the introduction of the long carbon chain fluorinated silane coupling agent not only reduces the surface energy of graphene, carbon nanotubes, and hollow glass microspheres, but also the entanglement of the long chain structure helps to connect the graphene, carbon nanotubes, and hollow glass microspheres, avoiding the agglomeration of a single material, improving its dispersion performance, and helping to improve the density and corrosion resistance of the coating. Hollow glass microspheres have a lower density and better suspension properties in water-based polyurethane coatings, which can promote the dispersion of graphene and carbon nanotubes, so that zero-dimensional particles, one-dimensional carbon nanotubes and two-dimensional graphene can construct a three-dimensional micro-nano rough structure on the coating surface, forming a solid-air-water contact pattern, thereby making the coating achieve superhydrophobic properties. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0031] The specific preparation process for long-chain fluorinated silane coupling agent-modified graphene in the following examples and comparative examples is as follows: the long-chain fluorinated silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, acetic acid is added to adjust the pH to 4, and hydrolysis is carried out at room temperature for 1.3 hours to obtain a mixed solution; graphene with an average lateral size of 3 μm is added to the mixed solution, stirred at 52°C for 7 hours, and then filtered, washed, and dried to obtain the long-chain fluorinated silane coupling agent-modified graphene. The mass ratio of the long-chain fluorinated silane coupling agent to graphene is 0.2:1; the long-chain fluorinated silane coupling agent is perfluorodecyltrimethoxysilane; and the volume ratio of ethanol to deionized water is 7:1.

[0032] The specific preparation process for carbon nanotubes modified with a long-chain fluorinated silane coupling agent in the following examples and comparative examples is as follows: the long-chain fluorinated silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, the pH is adjusted to 4.5 with acetic acid, and the mixture is hydrolyzed at room temperature for 1.6 hours to obtain a mixed solution; carbon nanotubes with an average length of 30 μm are added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain the long-chain fluorinated silane coupling agent-modified carbon nanotubes. The mass ratio of the long-chain fluorinated silane coupling agent to the carbon nanotubes is 0.25:1; the long-chain fluorinated silane coupling agent is perfluorodecyltrimethoxysilane; and the volume ratio of ethanol to deionized water is 7:1.

[0033] The coating preparation process in the following examples and comparative examples is as follows: long-chain fluorine-containing silane coupling agent-modified graphene, long-chain fluorine-containing silane coupling agent-modified carbon nanotubes, long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres, and deionized water are uniformly mixed, then an aqueous polyurethane dispersion is added, stirred and dispersed, and then an additive is added and mixed again to obtain a high-performance coating. In Comparative Examples 1-3, the components used in zero amounts are not added.

[0034] Subsequently, under the same conditions, the salt spray resistance of the high-performance coatings prepared in the examples and comparative examples was tested with reference to GB / T 1771-2007, and the contact angle of the coating was measured using a contact angle meter.

[0035] Example 1 A high-performance coating comprising the following components in parts by weight: 120 parts of aqueous polyurethane dispersion, 5 parts of graphene modified with a long-chain fluorinated silane coupling agent, 10 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 1 part of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 0.5 parts of BYK420, 0.5 parts of sodium polyacrylate, 0.5 parts of polydimethylsiloxane, and 60 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1 hour to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 45°C for 8 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.1:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1420 hours and a contact angle of 155.2°.

[0036] Example 2 A high-performance coating comprising the following components in parts by weight: 150 parts of aqueous polyurethane dispersion, 10 parts of graphene modified with a long-chain fluorinated silane coupling agent, 15 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 4 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 2.5 parts of BYK420, 2.5 parts of sodium polyacrylate, 2.5 parts of polydimethylsiloxane, and 100 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 2 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 55°C for 4 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.3:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1640 hours and a contact angle of 162.1°.

[0037] Example 3 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 15 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 2 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1660 hours and a contact angle of 158.4°.

[0038] Example 4 A high-performance coating comprising the following components in parts by weight: 125 parts of aqueous polyurethane dispersion, 10 parts of graphene modified with a long-chain fluorinated silane coupling agent, 10 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 4 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 0.5 parts of BYK420, 2.5 parts of sodium polyacrylate, 0.5 parts of polydimethylsiloxane, and 100 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1 hour to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 45°C for 4 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.28:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1570 hours and a contact angle of 159.6°.

[0039] Example 5 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 8 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 2 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.05:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1480 hours and a contact angle of 156.8°.

[0040] Example 6 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 6.5 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 2 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1 part of BYK420, 1 part of sodium polyacrylate, 1 part of polydimethylsiloxane, and 70 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.2 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 48°C for 7 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.15:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1460 hours and a contact angle of 157.1°.

[0041] Example 7 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 8 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 2 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.4:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1510 hours and a contact angle of 161.3°.

[0042] Example 8 A high-performance coating comprising the following components in parts by weight: 140 parts of aqueous polyurethane dispersion, 8.5 parts of graphene modified with a long-chain fluorinated silane coupling agent, 14 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 3 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 2 parts of BYK420, 2 parts of sodium polyacrylate, 2 parts of polydimethylsiloxane, and 90 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.8 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 52°C for 5 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.25:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1590 hours and a contact angle of 160.5°.

[0043] Example 9 A high-performance coating comprising the following components in parts by weight: 125 parts of aqueous polyurethane dispersion, 7.5 parts of graphene modified with a long-chain fluorinated silane coupling agent, 13.5 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 1.5 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.8 parts of BYK420, 1 part of sodium polyacrylate, 1.7 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.8 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 46°C for 7.5 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.13:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had salt spray resistance of 1600 hours and a contact angle of 161.6°.

[0044] Example 10 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 8 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 2 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1620 hours and a contact angle of 163.3°.

[0045] Comparative Example 1 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 0 parts of graphene modified with a long-chain fluorinated silane coupling agent, 18.9 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 3.1 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1010 hours and a contact angle of 135.6°.

[0046] Comparative Example 2 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 17.6 parts of graphene modified with a long-chain fluorinated silane coupling agent, 0 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 4.4 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1060 hours and a contact angle of 138.8°.

[0047] Comparative Example 3 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 8.8 parts of graphene modified with a long-chain fluorinated silane coupling agent, 13.2 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 0 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1240 hours and a contact angle of 131.2°.

[0048] Comparative Example 4 A high-performance coating comprising the following components in parts by weight: 130 parts of aqueous polyurethane dispersion, 8 parts of graphene modified with a long-chain fluorinated silane coupling agent, 12 parts of carbon nanotubes modified with a long-chain fluorinated silane coupling agent, 7 parts of hollow glass microspheres modified with a long-chain fluorinated silane coupling agent, 1.5 parts of BYK420, 1.5 parts of sodium polyacrylate, 1.5 parts of polydimethylsiloxane, and 80 parts of deionized water; the aqueous polyurethane dispersion has a solid content of 62%; The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: A long-chain fluorinated silane coupling agent was dispersed in a mixed solvent of ethanol and deionized water. The pH was adjusted to 4.5 with acetic acid, and the mixture was hydrolyzed at room temperature for 1.5 hours to obtain a mixed solution. Hollow glass microspheres with an average particle size of 15 μm were added to the mixed solution, stirred at 50°C for 6 hours, and then filtered, washed, and dried to obtain hollow glass microspheres modified with the long-chain fluorinated silane coupling agent. The mass ratio of the long-chain fluorinated silane coupling agent to the hollow glass microspheres was 0.2:1, and the volume ratio of ethanol to deionized water was 7:1. The long-chain fluorinated silane coupling agent was perfluorodecyltrimethoxysilane. Testing showed that the coating had a salt spray resistance of 1550 hours and a contact angle of 142.4°.

[0049] As can be seen from the above examples and comparative examples, the present invention adds two-dimensional flaky graphene modified with a long carbon chain fluorine-containing silane coupling agent, one-dimensional linear carbon nanotubes modified with a long carbon chain fluorine-containing silane coupling agent, and zero-dimensional granular hollow glass microspheres modified with a long carbon chain fluorine-containing silane coupling agent to waterborne polyurethane to construct a three-dimensional spatial structure. By compounding the three fillers of point, line, and surface, a micro-nano structure is successfully constructed on the coating surface, and the introduction of a perfluorosilane coupling agent further reduces the surface energy of the rough surface. The micro-nano structure plays a super-hydrophobic role, and the micron structure can play a protective role, preventing the nanostructure from being destroyed, thereby giving the coating good stability and improving its corrosion resistance. Compared with Example 10, Comparative Examples 1-3 lacked long-chain fluorinated silane coupling agent-modified graphene, long-chain fluorinated silane coupling agent-modified carbon nanotubes, and long-chain fluorinated silane coupling agent-modified hollow glass microspheres, respectively. Consequently, the filler's inherent properties failed to form a micro-nano rough structure on the coating surface, which in turn affected filler dispersion, resulting in reduced coating density, salt spray resistance, and decreased hydrophobicity. Comparative Example 4 employed an excessive amount of long-chain fluorinated silane coupling agent-modified hollow glass microspheres. While salt spray resistance did not change significantly, the excessive amount increased coating instability, hindering the formation of micro-nano structures on the coating surface. This resulted in a lower contact angle and reduced hydrophobicity.

[0050] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A high performance coating, characterized in that: Contains the following components in parts by weight: 120-150 parts of aqueous polyurethane dispersion, 5-15 parts of long-chain fluorinated silane coupling agent-modified graphene, 10-15 parts of long-chain fluorinated silane coupling agent-modified carbon nanotubes, 1-4 parts of long-chain fluorinated silane coupling agent-modified hollow glass microspheres, 1-8 parts of auxiliary agent, and 50-100 parts of solvent.

2. A high performance coating according to claim 1, characterized in that: The long-chain fluorine-containing silane coupling agent is one or more of perfluorodecyltrichlorosilane, perfluorodecyltrimethoxysilane, perfluorodecyltriethoxysilane, perfluorooctyltriethoxysilane, perfluorooctyltrimethoxysilane, and perfluorooctyltrichlorosilane.

3. A high performance coating according to claim 1, characterized in that: The auxiliary agent is one or more of an anti-settling agent, a defoaming agent, a wetting and dispersing agent, a leveling agent, a preservative, and an antibacterial agent.

4. A high performance coating according to claim 1, characterized in that: The solvent is deionized water.

5. A high performance coating according to claim 1, characterized in that: The preparation process of the hollow glass microspheres modified by the long-chain fluorine-containing silane coupling agent is as follows: The long-chain fluorine-containing silane coupling agent is dispersed in a mixed solvent of ethanol and deionized water, acid is added to adjust the pH, and hydrolysis is performed at room temperature to obtain a mixed solution; hollow glass microspheres are added to the mixed solution, stirred for reaction, and filtered, washed, and dried to obtain long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres.

6. A high performance coating according to claim 5, characterized in that: The mass ratio of the long-chain fluorine-containing silane coupling agent to the hollow glass microspheres is (0.05-0.4):

1.

7. A high performance coating according to claim 5, characterized in that: The acid is one or more of formic acid, acetic acid, citric acid, and lactic acid; and the pH is 3-5.

8. A high performance coating according to claim 5, characterized in that: The hydrolysis time is 1-2 hours; the stirring reaction temperature is 45-55° C., and the reaction time is 4-8 hours.

9. A high performance coating according to claim 1, characterized in that: The preparation method of the high performance coating comprises the following steps: After long-chain fluorine-containing silane coupling agent-modified graphene, long-chain fluorine-containing silane coupling agent-modified carbon nanotubes, long-chain fluorine-containing silane coupling agent-modified hollow glass microspheres and solvent are evenly mixed, aqueous polyurethane dispersion is added, stirred and dispersed, and then auxiliary agents are added and mixed evenly again to prepare a high-performance coating.

10. A color steel plate, characterized in that: The high-performance coating according to any one of claims 1 to 9 is applied on the surface of a cleaned color steel plate to obtain the coating.