Self-cleaning fluorocarbon coating and preparation method thereof

Abstract

The preparation method comprises the following steps: selecting monodisperse silicon dioxide microspheres, soaking the monodisperse silicon dioxide microspheres in absolute ethyl alcohol, stirring the monodisperse silicon dioxide microspheres for 1 hour, carrying out ultrasonic dispersion treatment for 2 hours, dropwise adding a silane coupling agent into the solution, carrying out stirring and ultrasonic treatment at the same time, and after the silane coupling agent is dropwise added, carrying out ultrasonic dispersion treatment at the same time; continuously carrying out ultrasonic dispersion for 1 hour to obtain a silane coupling agent modified silicon dioxide microsphere solution A; adding two or more silane coupling agent modified monodisperse silicon dioxide solutions with different particle sizes into acrylic resin heated in a water bath, continuously stirring and carrying out ultrasonic treatment for 2 hours to obtain a monodisperse silicon dioxide modified acrylic acid solution B; and S2, mixing and grinding acrylic resin, a PVDF resin film-forming material and an auxiliary agent in a solvent to prepare a PVDF fluorocarbon coating, gradually adding the monodisperse silicon dioxide modified acrylic acid solution obtained in the step S2 into the PVDF fluorocarbon coating, and uniformly stirring at a constant temperature to obtain the long-acting and stable self-cleaning PVDF fluorocarbon coating.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paint technology, in particular to a self-cleaning fluorocarbon paint and a preparation method thereof. BACKGROUND

[0002] Fluorocarbon paint is a series of coatings collectively referred to as fluorocarbon resin as the main film-forming material, which is a new type of coating paint processed by modification on the basis of fluorocarbon resin. Fluorocarbon paint has a history of more than 70 years in the United States, and various fluorocarbon paints of different brands and different purposes have been developed in the United States, Japan and other countries. At present, there are hundreds of millions of square meters of buildings in the world using this coating. For example, Japan started to grow at a rate of 20% to 50% per year in the 1980s, and now still maintains a growth rate of 10%. Fluorocarbon paint has been widely used in China since 1993, and has developed faster in recent years, especially PVDF and FEVE fluorocarbon paint.

[0003] The domestic market demand for coatings is developing towards high decorative, high weather resistance, high functionality and low pollution, which will inevitably provide a good opportunity for the rapid development of fluorocarbon paint with super long weather resistance, color variety and long service life.

[0004] Polyvinylidene fluoride (PVDF) fluorocarbon paint has been successfully used in harsh environments around the world for more than 40 years, which shows that PVDF fluorocarbon coating can improve the weather resistance of buildings by several times to several tens of times, and is the best coating. At present, the application form of PVDF fluorocarbon paint at home and abroad is still mainly solvent type, mainly because the construction process of solvent type PVDF fluorocarbon paint is relatively mature, and the coating performance is excellent. With the improvement of people's living standards, the requirements for PVDF fluorocarbon paint are getting higher and higher, especially the PVDF fluorocarbon paint used in high-rise buildings, which requires the coating performance to have long-acting self-cleaning effect while maintaining the original performance.

[0005] In the prior art, there are two types of self-cleaning coatings, the first type is super-hydrophobic self-cleaning coating, and the second type is super-hydrophilic self-cleaning coating. The super-hydrophobic self-cleaning coating constructs a multi-level rough structure similar to the surface of a lotus leaf by using fluorinated titanium dioxide nanoparticles (particle size 20-50mm), so that the water contact angle is more than 150°, and the water droplets roll in a spherical shape and carry away the pollutants. The super-hydrophilic self-cleaning coating utilizes the active oxygen produced by nano-titanium dioxide under ultraviolet excitation to decompose organic matter into carbon dioxide and water, with a decomposition efficiency of 46%, and the coating surface contact angle is less than 20°. When the rain washes, a water film is formed to spread evenly, carrying away the degraded pollutants.

[0006] The patent with publication number CN109294352A discloses a self-cleaning water-based fluorocarbon building coating and a preparation method, and specifically discloses a method for forming a hydrophobic particle self-cleaning water-based fluorocarbon building coating. The nano silicon dioxide is modified by a silane coupling agent, and aluminum hydroxide is added alternately to combine the nano silicon dioxide and the silane coupling agent into a hydrophobic type, and then the hydrophobic type is coated with a surfactant and dispersed in water, combined with the water-based fluorocarbon coating, which greatly improves the optical performance, anti-aging performance and wash resistance of the fluorocarbon coating, and has excellent self-cleaning performance. The initial water contact angle is 32°-36°, the oil contact angle is 166°-172°, after 10 times of water resistance cycle test, the water contact angle is 35°-41°, and the oil contact angle is 161°-166°. The scheme discloses a super-hydrophobic self-cleaning coating. According to the contact angle detection data, the self-cleaning performance of the self-cleaning fluorocarbon coating is not outstanding, and long-term self-cleaning cannot be achieved, so it needs to be improved.

[0007] The patent with publication number CN111004531A discloses a self-cleaning building coating, and specifically discloses that the water-soluble acrylic resin, the curing agent, the surfactant and the nano titanium dioxide cooperate to maintain the good sustained hydrophilicity of the coating. The nano TiO2 is a N semiconductor material, and there is a forbidden band between the valence band full of electrons and the conduction band composed of holes. When the energy of the ultraviolet light irradiated on the surface of the nano TiO2 film is greater than the forbidden band width, the electrons in the valence band of the nano TiO2 are excited and jump to the conduction band, and at the same time, the holes are formed in the valence band. The electrons in the conduction band react with O2 in the air to generate superoxide anion (O 2- ); the holes in the valence band adsorb H2O to form hydroxyl radicals. The hydroxyl radicals have strong oxidizing property and can degrade various organic matters adsorbed on the surface of the nano TiO2 coating film into H2O and CO2, realizing strong and long-lasting self-cleaning performance. Under the cooperation of the water-soluble acrylic resin, the curing agent and the surfactant, a small amount of nano TiO2 can achieve 5-10 times self-cleaning effect, effectively reducing the cost. The methyl methacrylate, butyl acrylate, hydroxyethyl acrylate and initiator do not contain fluorine and other low surface materials, are green and environmentally friendly, and have the characteristics of weather resistance, stain resistance and scratch resistance, so that the self-cleaning ability of the coating is reliable. The coating disclosed in the scheme is a super-hydrophilic self-cleaning coating, which mainly uses superoxide anion to decompose organic matter. Although the amount of nano titanium dioxide is reduced to reduce the cost, the use effect is affected by the intensity of ultraviolet light, the self-cleaning performance of the coating is poor, and the decomposition efficiency is usually below 46%, and long-term self-cleaning cannot be achieved. SUMMARY

[0008] The first inventive object of the present application is to solve the problem of poor self-cleaning effect of the existing self-cleaning coating and the problem of inability to achieve long-acting self-cleaning effect, and to provide a preparation method of self-cleaning fluorocarbon coating.

[0009] To achieve the above object, the present application is implemented by the following technical solutions: The preparation method of the self-cleaning fluorocarbon coating comprises the following steps: S1: selecting monodisperse silica microspheres, soaking in anhydrous ethanol for stirring for 1 hour, and then performing 2h ultrasonic dispersion treatment; dropping silane coupling agent into the above solution while stirring and ultrasonicating; after the dropping of the silane coupling agent is completed, continuing to perform 1h ultrasonic dispersion to obtain a silane coupling agent modified silica microsphere solution A; S2: taking two or more different particle size silane coupling agent modified monodisperse silica solutions and adding them into the water-bath-heated acrylic resin, continuing to stir and ultrasonicate for 2 hours to obtain a monodisperse silica modified acrylic solution B; S3: mixing and grinding the acrylic resin with PVDF resin film-forming material and additives in a solvent to prepare a PVDF fluorocarbon coating, and then gradually adding the monodisperse silica modified acrylic solution obtained in step S2 into the PVDF fluorocarbon coating, and uniformly stirring at constant temperature to obtain a self-cleaning PVDF fluorocarbon coating.

[0010] In the above scheme, the silica is uniform monodisperse silica microspheres, and the particle size of the monodisperse silica microspheres is 5-40μm.

[0011] In the above scheme, the silane coupling agent is one or several of KH550, KH560 and KH570.

[0012] In the above scheme, in step S2, the silane coupling agent modified monodisperse silica microspheres added into the acrylic resin include two particle sizes, the particle size of the first kind of particles D1 is 5-15 microns, and the particle size of the second kind of particles D2 is 20-40 microns, and the corresponding weight ratio is D1:D2=5-50:1.

[0013] In the above scheme, in step S2, the silane coupling agent modified monodisperse silica microspheres added into the acrylic resin include two particle sizes, the particle size of the first kind of particles D1 is 8-15 microns, and the particle size of the second kind of particles D2 is 25-30 microns, and the corresponding weight ratio is D1:D2=20-30:1.

[0014] In the above scheme, in step S2, the weight ratio of the silane coupling agent modified monodisperse silica microspheres to the acrylic resin added into the acrylic resin is 1:10-50.

[0015] In the above scheme, in the step S3, the weight ratio of the monodisperse silica modified acrylic acid to the PVDF fluorocarbon paint is 1:80-200.

[0016] A second object of the present application is to provide a self-cleaning fluorocarbon paint with long-acting self-cleaning performance prepared by the above preparation method.

[0017] The present application has the following positive effects: the preparation method of the self-cleaning fluorocarbon paint of the present application uses micron-sized monodisperse silica microspheres, and the monodisperse silica microspheres are modified by a silane coupling agent to obtain solution A, and then the solution A of the above silane coupling agent modified monodisperse silica microspheres with two or more particle sizes is used to modify an acrylic resin to obtain solution B, and then the PVDF fluorocarbon paint is prepared using the acrylic resin and a PVDF resin film-forming material and an additive, so that the PVDF fluorocarbon paint can be better compatible with the solution B, and the super-hydrophobic self-cleaning paint is prepared, and the self-cleaning fluorocarbon paint prepared contains at least two particle sizes of SixOx-1(OH)y(OR)zalcoholic sol, and the formed coating surface has a hydrophobic rough surface, and the coating prepared by the self-cleaning fluorocarbon paint of the present application has a water contact angle of 165°-172°, and when it rains, the rainwater can roll along the coating surface in a nearly spherical shape to clean the dust on the coating surface. The self-cleaning fluorocarbon paint of the present application can stably bond with the building outer wall and is not easy to fall off, and the particles in the coating are also not easy to separate and fall off, and the coating can be stably attached to the outer wall surface of the building for a long time, and the coating has long-acting self-cleaning performance, and can maintain the self-cleaning performance for a long time under the natural rain environment. DETAILED DESCRIPTION

[0018] The technical solutions of the present application will be described below by examples, and obviously, the described examples are only a part of the examples of the present application, but not all the examples. Based on the examples in the present application, all the other examples obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0019] Example 1 A preparation method of a self-cleaning fluorocarbon paint, which comprises the following steps: S1: two kinds of monodisperse silica microspheres with different particle sizes are selected, and are respectively soaked in anhydrous ethanol for stirring for 1 hour, and then are subjected to 2h ultrasonic dispersion treatment, and a silane coupling agent is added dropwise into the above solution while stirring and ultrasonic treatment, and after the addition of the silane coupling agent is completed, the ultrasonic dispersion is continued for 1h to obtain a solution A of the silane coupling agent modified silica microspheres; Two kinds of silane coupling agent modified silica microspheres solution D1 and D2 are prepared by using two different particle sizes to prepare two single-dispersed silica microspheres. Solution D1 uses single-dispersed silica microspheres with a particle size of 5 microns, and solution D2 uses single-dispersed silica microspheres with a particle size of 20 microns. When preparing solution D1, 600 ml of anhydrous ethanol solution is added to a container bottle, then 60 g of single-dispersed silica microspheres with a particle size of 5 microns is added, stirred for 1 hour, and then subjected to 2h ultrasonic stirring and dispersion treatment; then 4.5 g of silane coupling agent KH560 is gradually added to the above solution, and stirring and ultrasonic treatment are carried out at the same time, and after the silane coupling agent is added, 1h ultrasonic dispersion is continued, and then the silane modified silica microspheres solution D1 is obtained. When preparing solution D2, 120 ml of anhydrous ethanol solution is added to a container bottle, then 12 g of single-dispersed silica microspheres with a particle size of 20 microns is added, stirred for 1 hour, and then subjected to 2h ultrasonic stirring and dispersion treatment; then 0.9 g of silane coupling agent KH560 is gradually added to the above solution, and stirring and ultrasonic treatment are carried out at the same time, and after the silane coupling agent is added, 1h ultrasonic dispersion is continued, and then the silane modified silica microspheres solution D2 is obtained.

[0020] S2 The two kinds of silane coupling agent modified single-dispersed silica solution D1 and D2 prepared in step S1 are added to the acrylic acid resin heated in the water bath, and stirring and ultrasonic treatment are continued for 2 hours to obtain a single-dispersed silica modified acrylic acid solution B; wherein the mass ratio of solution A to acrylic acid resin is 1:10; for example, the mass ratio of D1 to D2 is 5:1, the mass of D1 solution added is 60 g, the mass of D2 solution added is 12 g, and the mass of acrylic acid resin added is 720 g.

[0021] S3 The acrylic acid resin is mixed with the PVDF resin film forming material and the auxiliary agent in the solvent to prepare a PVDF fluorocarbon coating C, and then the single-dispersed silica modified acrylic acid solution B obtained in step S2 is gradually added to the PVDF fluorocarbon coating C, wherein the mass ratio of the single-dispersed silica modified acrylic acid solution B to the PVDF fluorocarbon coating C is 1:80, and constant temperature stirring is uniformly carried out, and then a self-cleaning PVDF fluorocarbon coating is obtained.

[0022] Example 2 A method for preparing a self-cleaning fluorocarbon coating, comprising the following steps: S1 two different particle sizes of the preparation of two monodisperse silica microspheres prepared two kinds of silane coupling agent modified silica microspheres solution D1 and D2, solution D1 is used to prepare monodisperse silica microspheres with a particle size of 15 microns, solution D2 is used to prepare monodisperse silica microspheres with a particle size of 40 microns. When preparing solution D1, 1000 ml of anhydrous ethanol solution was added to a container bottle, then 100 g of monodisperse silica microspheres with a particle size of 15 microns was added, stirred for 1 hour and then dispersed by ultrasonic stirring for 2 hours; then 7.5 g of silane coupling agent KH560 was gradually added to the above solution, and stirring and ultrasonic were carried out at the same time, and after the silane coupling agent was added, ultrasonic dispersion was continued for 1 hour, and the silane modified silica microsphere solution D1 was obtained. When preparing solution D2, 120 ml of anhydrous ethanol solution was added to a container bottle, then 5 g of monodisperse silica microspheres with a particle size of 40 microns was added, stirred for 1 hour and then dispersed by ultrasonic stirring for 2 hours; then 0.375 g of silane coupling agent KH560 was gradually added to the above solution, and stirring and ultrasonic were carried out at the same time, and after the silane coupling agent was added, ultrasonic dispersion was continued for 1 hour, and the silane modified silica microsphere solution D2 was obtained.

[0023] S2 two kinds of particle size of the silane coupling agent modified monodisperse silica solution D1 and D2 prepared in step S1 are added to the acrylic resin heated in water bath, and stirring and ultrasonic are continued for 2 hours to obtain monodisperse silica modified acrylic solution B; wherein the mass ratio of solution A to acrylic resin is 1:30; for example, the mass ratio of D1 to D2 is 20:1, the mass of D1 added is 100 g, the mass of D2 added is 5 g, and the mass of acrylic resin added is 3150 g.

[0024] S3 acrylic resin and PVDF resin film forming material, additives are mixed and ground in solvent to prepare PVDF fluorocarbon coating C, and then monodisperse silica modified acrylic solution B obtained in step S2 is gradually added to PVDF fluorocarbon coating C, wherein the mass ratio of monodisperse silica modified acrylic solution B to PVDF fluorocarbon coating C is 1:100, and constant temperature stirring is uniform, and self-cleaning PVDF fluorocarbon coating is obtained.

[0025] Example 3 A preparation method of a self-cleaning fluorocarbon coating, comprising the following steps: S1 two different particle size of the preparation of two monodisperse silica microspheres prepared two kinds of silane coupling agent modified silica microspheres solution D1 and D2, solution D1 using particle size of 8 microns of monodisperse silica microspheres, solution D2 using particle size of 30 microns of monodisperse silica microspheres. Preparation of solution D1, in the container bottle is added to 1000 ml of anhydrous ethanol solution, then add 100 g of particle size of 8 microns of monodisperse silica microspheres, stirring for 1 hour and then 2 h ultrasonic stirring dispersion treatment; then the 7.5 g of silane coupling agent KH560 is gradually added to the above solution, while stirring and ultrasonic, after the silane coupling agent drop is completed need to continue for 1 h ultrasonic dispersion, namely the silane modified silica microspheres solution D1. Preparation of solution D2, in the container bottle is added to 20 ml of anhydrous ethanol solution, then add 2 g of particle size of 30 microns of monodisperse silica microspheres, stirring for 1 hour and then 2 h ultrasonic stirring dispersion treatment; then the 0.15 g of silane coupling agent KH560 is gradually added to the above solution, while stirring and ultrasonic, after the silane coupling agent drop is completed need to continue for 1 h ultrasonic dispersion, namely the silane modified silica microspheres solution D2.

[0026] S2 to step S1 prepared two kinds of particle size of the silane coupling agent modified monodisperse silica solution D1 and D2 is added to the water bath heating of acrylic resin, continue to stir and ultrasonic 2 hours, obtain monodisperse silica modified acrylic solution B; wherein the mass ratio of solution A and acrylic resin is 1:50; for example, the mass ratio of D1 and D2 is 50:1, the mass of D1 is 100 g, the mass of D2 is 2 g, the mass of acrylic resin is 5100 g.

[0027] S3 acrylic resin and PVDF resin film forming material, additives in the solvent grinding, prepared PVDF fluorocarbon paint C, then the step S2 obtained monodisperse silica modified acrylic solution B is gradually added to the PVDF fluorocarbon paint C, wherein the mass ratio of monodisperse silica modified acrylic solution B and PVDF fluorocarbon paint C is 1:200, constant temperature stirring uniform, namely the self cleaning PVDF fluorocarbon paint can be obtained.

[0028] In addition to fluorocarbon resin, the film-forming component used in the self-cleaning fluorocarbon coatings of Examples 1-3 of the present invention can also be any film-forming component known to those skilled in the art, such as thermosetting acrylic resin, thermoplastic acrylic resin, etc. Preferably, the film-forming component is PVDF fluorocarbon resin. The fluorocarbon resin used in the present invention is well known to those skilled in the art, and examples include polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoroethylene-propylene copolymer, tetrafluoroethylene-vinylidene fluoride-acrylic acid copolymer, etc. Preferably, the fluorocarbon resin used in the present invention is selected from polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer, and tetrafluoroethylene-vinylidene fluoride-acrylic acid copolymer.

[0029] The self-cleaning fluorocarbon coatings in Examples 1-3 of the present invention further comprise solvents. The solvents used are common solvents or mixtures thereof, including but not limited to aromatics such as xylene and toluene; esters such as ethyl acetate, butyl acetate, and isoamyl acetate; alcohols such as butanol, isobutanol, and benzyl alcohol; ethers such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and propylene glycol diethyl ether; and ketones such as methyl isobutyl ketone, acetophenone, and isophorone. Those skilled in the art can determine the amount of solvent used according to the desired properties of the coatings according to the present invention, such as coating performance.

[0030] The self-cleaning fluorocarbon coatings in Examples 1-3 of the present invention may also contain other components known to those skilled in the art, such as silane coupling agents, defoamers, wetting agents, dispersants, emulsifiers, anti-settling agents, stabilizers, anti-skinning agents, leveling agents, drying agents, anti-sagging agents, plasticizers, matting agents, flame retardants, mildew inhibitors, bactericides, and trapping agents. Those skilled in the art can determine the specific types and amounts of the other components used according to the desired properties of the coatings according to the present invention, such as bactericidal properties.

[0031] The coating of the present invention is obtained by mixing the SixOx-1(OH)y(OR)z alcohol sol prepared as described above, the film-forming component, optional pigments and fillers, and optional additives in a solvent, wherein the weight ratio of SixOx-1(OH)y(OR)z alcohol sol, based on silica, to the film-forming component is 1:15-85, preferably 1:20-65, and more preferably 1:25-50.

[0032] Comparative Example 1 Following the method in step S1 of Example 1, a silane coupling agent modified silica microsphere solution A was prepared using monodisperse silica microspheres with a particle size of 20 micrometers. Solution B was prepared by mixing solution A with acrylic resin at a ratio of 1:30, following the method in step S2 of Example 1. Then, a self-cleaning fluorocarbon coating was prepared by mixing solution B with PVDF fluorocarbon coating C at a ratio of 1:100, following the method in step S3 of Example 1.

[0033] Comparative Example 2 The monodisperse silica microspheres solution A was prepared by the method of step S1 in the preceding Example 1 using monodisperse silica microspheres with a particle size of 20 microns, and the hydroxyethyl cellulose was dissolved in water to obtain solution B; the wetting dispersant was mixed uniformly with solution A to obtain solution C; solution C contained 4 parts by weight of wetting dispersant and 84 parts by weight of solution A; solution B, solution C, inorganic pigment and water were mixed uniformly at room temperature, and the ground inorganic filler was added to obtain slurry D; under stirring, wetting dispersant was added again to slurry D, and mixed uniformly with defoaming agent, bactericide, aqueous fluorocarbon emulsion, film-forming aid, thickening agent and water to obtain the self-cleaning aqueous fluorocarbon architectural coating.

[0034] Test Experiment 1 The coatings prepared in Examples 1-3 and Comparative Examples 1-2 were uniformly applied to the surface of concrete with an average thickness of 0.25 mm, and the water contact angle was measured using a contact angle tester, then the sample was immersed in water for 8 h, and after being taken out, it was dried by blowing air, which was one cycle, and after 10 cycles, the water contact angle was tested again, and the test results are shown in the following table: .

[0035] Test Experiment 2 The coatings prepared in Examples 1-3 and Comparative Examples 1-2 were uniformly applied to the surface of concrete with an average thickness of 0.25 mm, and a line was drawn on the surface of the coating with a marker pen, and then the coating was washed with clean water for 10 minutes, and after washing, it was observed whether there were traces of the drawn line on the surface of the coating. The test results are shown in the following table: .

[0036] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a self-cleaning fluorocarbon coating, characterized in that, It comprises the following steps: S1: Selecting monodisperse silica microspheres, soaking in anhydrous ethanol for 1 hour, then performing 2h ultrasonic dispersion treatment, adding silane coupling agent to the above solution, stirring and ultrasonic treatment at the same time, continuing ultrasonic dispersion for 1h after the completion of silane coupling agent dropwise addition, obtaining silane coupling agent modified silica microsphere solution A; S2: Taking two or more different particle size silane coupling agent modified monodisperse silica solutions into the acrylic resin heated in a water bath, continuing to stir and ultrasonic for 2 hours, obtaining monodisperse silica modified acrylic solution B; S3: Mixing and grinding acrylic resin with PVDF resin film forming material and additives in a solvent to prepare PVDF fluorocarbon coating, then gradually adding the monodisperse silica modified acrylic solution obtained in step S2 into the PVDF fluorocarbon coating, stirring uniformly at constant temperature, obtaining self-cleaning PVDF fluorocarbon coating.

2. The method of claim 1, wherein the self-cleaning fluorocarbon coating is prepared by: The silica is uniform monodisperse silica microspheres, and the particle size of the monodisperse silica microspheres is 5-40μm.

3. The method for preparing the self-cleaning fluorocarbon coating according to claim 1, characterized in that: The silane coupling agent is one or several of KH550, KH560 and KH570.

4. The method of claim 1, wherein the self-cleaning fluorocarbon coating is prepared by: In step S2, the silane coupling agent modified monodisperse silica microspheres added to the acrylic resin include two particle sizes, the particle size of the first particle D1 is 5-15 microns, and the particle size of the second particle D2 is 20-40 microns, and the corresponding weight ratio is D1: D2 = 5-50:

1.

5. The method of claim 4, wherein the self-cleaning fluorocarbon coating is prepared by: In step S2, the silane coupling agent modified monodisperse silica microspheres added to the acrylic resin include two particle sizes, the particle size of the first particle D1 is 8-15 microns, and the particle size of the second particle D2 is 25-30 microns, and the corresponding weight ratio is D1: D2 = 20-30:

1.

6. The method of claim 1, wherein the self-cleaning fluorocarbon coating is prepared by: In step S2, the weight ratio of the silane coupling agent modified monodisperse silica microspheres to the acrylic resin is 1: 10-50.

7. The method for preparing the self-cleaning fluorocarbon coating according to claim 1, characterized in that: In step S3, the weight ratio of the monodisperse silica modified acrylic to the PVDF fluorocarbon coating is 1: 80-200.

8. A self-cleaning fluorocarbon coating prepared by the method of any one of claims 1 to 7, characterized by: Prepared by the preparation method. Prepared by the preparation method.