CN108893052B

CN108893052B - Water-based super-hydrophobic coating and preparation method thereof

Info

Publication number: CN108893052B
Application number: CN201810506276.5A
Authority: CN
Inventors: 张旭; 刘景新; 王小梅
Original assignee: Hebei University of Technology
Current assignee: Hebei University of Technology
Priority date: 2018-05-24
Filing date: 2018-05-24
Publication date: 2020-10-27
Anticipated expiration: 2038-05-24
Also published as: CN108893052A

Abstract

The invention relates to a water-based super-hydrophobic coating and a preparation method thereof. The coating comprises the following raw materials in percentage by mass: 1-20% of hydrophobic resin, 10-90% of good solvent of the hydrophobic resin, 0.01-1% of additive, 0.1-10% of nano-particles and the balance of water. The additive is a curing agent or adhesive resin; the hydrophobic resin is one or more of organic silicon resin, fluorocarbon resin, fluorinated modified epoxy resin and fluorinated modified polyurethane. The nano particles are one or more of fumed silica, nano titanium dioxide, nano alumina, fluorine modified nano silica and alkyl modified nano silica. The invention has the advantages of easily obtained raw materials and simple preparation conditions, and can treat various substrates by a simple dip-coating or spraying process and further solidify to obtain the super-hydrophobic surface.

Description

Water-based super-hydrophobic coating and preparation method thereof

Technical Field

The invention belongs to the technical field of preparation methods of functional coatings, and particularly relates to a water-based super-hydrophobic coating and a preparation method thereof.

Background

The super-hydrophobic state is defined as a super-wetting state that the static contact angle of a small water drop on a hydrophobic surface is more than 150 degrees, and the rolling angle is less than 10 degrees. The lotus leaf surface, the water strider leg, the butterfly wing, the rose petal and the like in nature have excellent super-hydrophobicity due to unique micron/nanometer grading coarse structure and chemical composition on the surfaces, so that the lotus leaf surface, the water strider leg, the butterfly wing, the rose petal and the like have survival advantages under certain environmental conditions. Based on the bionic theory, the preparation research of the super-hydrophobic surface is a great hot spot recently. The super-wetting characteristic of the super-hydrophobic surface enables the super-hydrophobic material to have the functions of self-cleaning, drag reduction, water prevention, fog prevention, icing prevention, micro-fluidic control and the like, and the super-hydrophobic material has wide application prospects in the fields of aviation, navigation, energy, buildings, electronics, corrosion prevention, sensors, fluid transportation and the like.

The characteristics of superhydrophobicity are determined by the chemical composition and roughness of the material surface, and low surface free energy and proper roughness are two indispensable factors for preparing the superhydrophobic surface. Based on this theory, researchers have developed many methods to prepare superhydrophobic surfaces, which can be largely classified into two categories. One is a "top-down" method, including plasma etching, wet etching, machining, imprinting, laser ablation, etc.; the other is a "bottom-up" method, which includes electrostatic spinning, electrochemical oxidation, chemical oxidation, hydrothermal synthesis, sol-gel, spray coating, and the like. However, most of the existing methods have the limitations of expensive production equipment, high raw material price, long preparation process, complex process and the like, and the conversion from laboratory preparation to large-scale production application is difficult to realize.

Composite coatings are increasingly being used to treat a variety of substrates to obtain surfaces with superhydrophobicity because of their ease of mass production and application. Parkin et al first coat a layer of adhesive on the substrate, then coat the ethanol dispersion of titanium dioxide particle modified by fluorine-containing coupling agent, dry and get the hydrophobic and oleophobic super-amphiphobic coating. Patent CN105085953A utilizes a phase separation method to uniformly mix a good solvent and a poor solvent, then dissolves polylactic acid in the mixed solvent to prepare a pre-coating solution, and then adds the poor solvent to prepare a coating solution, and the coating solution is coated and dried on a substrate to obtain the polylactic acid super-hydrophobic film. Wherein the good solvent and the poor solvent are volatile organic solvents. CN101962514A dissolves and disperses the low surface energy polymer, the nano particles with photocatalytic activity and the cross-linking agent in an organic solvent, combines the low surface energy polymer and the inorganic nano particles through the cross-linking agent, and dries and solidifies at room temperature to obtain the super-hydrophobic coating. In patent CN106118356A, benzotriazole and mesoporous silica hollow spheres are used to prepare composite powder, silane coupling agent and aluminum borate whisker are used to prepare composite sol by adjusting pH, and then the powder, the sol and several emulsifiers are mixed to obtain the nano aluminum nitride modified bronze sculpture super-hydrophobic anticorrosive paint.

The method has the problems of complex process, large organic solvent consumption or dependence on auxiliary agents such as an emulsifier and the like, so that the development of the super-hydrophobic coating with simple process and environmental friendliness has great significance.

Disclosure of Invention

The invention aims to provide a water-based super-hydrophobic coating and a preparation method thereof aiming at the defects in the prior art. The method utilizes water with the proportion reaching 8% -85% in a dispersion system, replaces a common volatile organic solvent in the prior art, and accords with the trend of environmental protection; in addition, by selecting organic solvents such as tetrahydrofuran and the like which can be mixed and dissolved with water, a stable emulsion can be obtained without an emulsifier (which is not environment-friendly); and finally, water is added into the dispersion liquid in an ultrasonic environment, so that the controllable preparation of the quantity and the size of the dispersed phase liquid drops is realized. In the coarse structure required by the super-hydrophobic surface obtained by the invention, the hydrophobic resin coats the nano-particles, so that the particles are not exposed and can be both hydrophobic and hydrophilic.

The technical scheme adopted by the invention is as follows:

a water-based super-hydrophobic coating comprises the following raw materials in percentage by mass: 1-20% of hydrophobic resin, 10-90% of good solvent of the hydrophobic resin, 0.01-1% of additive, 0.1-10% of nano-particles and the balance of water.

The additive is a curing agent or adhesive resin.

The hydrophobic resin is one or more of organic silicon resin, fluorocarbon resin, fluorinated modified epoxy resin and fluorinated modified polyurethane.

The good solvent of the hydrophobic resin is one or more of methanol, ethanol, isopropanol, tetrahydrofuran, acetone, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone.

The adhesive resin is one or more of polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate and glyceryl polymethacrylate.

The nano particles are one or more of fumed silica, nano titanium dioxide, nano alumina, fluorine modified nano silica and alkyl modified nano silica, and the particle size of the particles is 5nm-300 nm.

The curing agent is one or more of vinyl-terminated siloxane, organic polyisocyanate and amino resin.

The preparation method of the water-based super-hydrophobic coating comprises the following steps:

step 1, dissolving hydrophobic resin and a curing agent in a good solvent according to the proportion to obtain a hydrophobic resin solution.

And 2, adding the additive and the nano particles into the hydrophobic resin solution obtained in the step 1, and dispersing for 1-30 min at a high speed by using a high-speed disperser to obtain a uniformly mixed suspension.

And 3, placing the suspension obtained in the step 2 into a container, immersing the container into ultrasonic water bath, ultrasonically dispersing, dropwise adding distilled water into the suspension, and finishing dropping at a constant speed within 10-180 min to obtain emulsion, namely the water-based super-hydrophobic coating.

In step 2, the working speed of the high-speed disperser is 2000r/min-8000 r/min.

In step 3, the frequency of the ultrasonic water bath is 20KHz-100KHz, and the temperature of the water bath is 5 ℃ to 75 ℃.

The application of the water-based super-hydrophobic coating comprises the following steps:

and 4, dip-coating or spray-coating the cleaned substrate with the emulsion obtained in the step 3, and drying and curing at 50-150 ℃ for 10-180 min to form the super-hydrophobic coating on the substrate.

In step 4, the substrate is a material with a rough surface, such as textile, building exterior wall, wooden equipment, paper, metal, etc. The specific cleaning process varies slightly depending on the characteristics of the actual material.

In the step 4, when the dip coating treatment is carried out, the soaking time is 5min-60 min; when the spraying treatment is carried out, the spraying angle is 60-90 degrees, the spraying distance is 10-35 cm, the spraying pressure is 0.1-0.6 MPa, and the substrate temperature is 20-100 ℃.

The invention has the substantive characteristics that:

in the water-based paint system prepared by the method, water is not used as a small-amount added auxiliary agent, but is used as a main body of a dispersing agent. The paint system is not added with a surfactant, but a proper organic solvent which can be mixed and dissolved with water is selected, the hydrophobic resin is firstly dissolved, then water is dripped, and the water and the good organic solvent have emulsification effect on the synergistic effect of the hydrophobic resin molecules. The hydrophobic resin can be dispersed into uniform emulsion, and is heated, dried and cured after being coated on the base material, and the hydrophobic resin liquid drops can not be migrated and fused greatly in the shorter drying and curing process, and basically keep the dispersed state, and finally form a coarse structure on the surface of the base material. The rough surface formed by resin curing is mainly a micron-scale rough structure, and a certain amount of nano particles are dispersed in emulsion droplets formed by adding nano particles, so that the nano-scale rough structure is increased by dispersing nano particles in the finally cured rough resin. The nanoparticles have high surface activity due to their small size effect and tend to aggregate over time in the dispersed phase, and their aggregation is limited by the coating of the dispersed large resin particles, thereby preserving the functionality of the nanoparticles. The micro/nano graded coarse structure can greatly increase the super-hydrophobicity of the surface, and can still keep enough roughness when the super-hydrophobic surface is subjected to external abrasion, so that the durability of the coating is greatly improved. The nano particles are uniformly dispersed in the hydrophobic resin, so that the nano roughness can be increased to enhance the super hydrophobicity, the strength is increased, the creep resistance of the resin is improved, and the service cycle of the functional coating is prolonged. Since the nanoparticles exerting the above effects are coated in the hydrophobic resin without directly contacting with water, the chemical composition of the nanoparticles is not critical in the present coating system, and fluorine-modified, alkyl-modified hydrophobic nanoparticles may be used, or unmodified hydrophilic nanoparticles may be used.

The invention has the beneficial effects that:

1. the water-based super-hydrophobic coating and the preparation method thereof provided by the invention have the advantages that the used raw materials are easy to obtain, the preparation conditions are simple, and various substrates can be treated by a simple dip-coating or spraying process and then cured to obtain the super-hydrophobic surface. The contact angle of water on the surface is about 160 degrees as shown in figure 2 and figure 3. Meanwhile, for the device subjected to spray coating treatment, the coating thickness can be increased in a repeated spray coating-curing mode, and the durability of the super-hydrophobic coating is improved.

2. The organic solvent selected by the invention can be mixed and dissolved with water, and has low toxicity and little environmental pollution compared with organic solvents such as benzene and the like used for traditional coatings. And water in the coating is a main dispersant, so that the influence on the environment is greatly reduced.

3. The superhydrophobic coating is prepared in which the hydrophobic resin is present in the form of small droplets, as shown in fig. 4, with droplet diameters between a few microns and tens of microns. The quantity and size of liquid drops in the emulsion can be adjusted by adjusting the concentration of the hydrophobic resin and the proportion of the organic solvent and the water, and the surface structure after coating and curing can be properly regulated and controlled, so that the performance of the coating is optimized.

4. The nano particles are added into the solution of the hydrophobic resin, and in the final coating, the hydrophobic resin is coated with the nano particles, so that the nano-scale rough structure is increased, and the super hydrophobicity is enhanced. As shown in the attached figure 1, the surface of the cloth fiber after coating treatment is adhered with hydrophobic resin projections with larger size, and small-sized nano particles are coated in the resin projections, so that a micro-nano graded coarse structure is formed on the surface of the fiber, and the super hydrophobicity is enhanced. After the nano particles are added, the transparency of the coating is slightly reduced, but the internal structure of the coating compounded with the nano particles is more stable, and the wear resistance is enhanced.

Drawings

FIG. 1 is a scanning electron micrograph of the surface of the superhydrophobic fabric of example 1;

FIG. 2 is a photograph showing the contact angle of the surface of the superhydrophobic fabric in example 2;

FIG. 3 is a photograph showing the contact angle of the superhydrophobic surface of the architectural wall sample of example 3;

FIG. 4 is a photograph taken by means of an optical microscope of the coating emulsion of example 4.

Detailed Description

The present invention will be described in detail with reference to specific examples.

The fumed silica, the nano titanium dioxide, the nano alumina, the fluorine modified nano silica and the alkyl modified nano silica related to the invention are all commercially known materials.

Example 1

Hydrophobic organic silicon resin prepolymer (Sylgard 184A, Dow Corning) and curing agent (Sylgard184B, Dow Corning) thereof are dissolved in good solvent tetrahydrofuran, fumed silica (particle size 7nm-13nm) is added after complete dissolution, and the mixture is dispersed for 5min at the rotating speed of 5000r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 25KHz, dropwise adding distilled water in 30 deg.C water bath, and completing dripping within 30min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 1% of hydrophobic organic silicon resin, 0.3% of curing agent, 30% of tetrahydrofuran, 0.2% of fumed silica and the balance of water.

And (3) soaking the cleaned nylon fabric into the dispersed emulsion for 30min at the system temperature of 30 ℃, taking out the fabric, extruding and removing the redundant coating, and drying and curing for 30min at the temperature of 60 ℃ to obtain the nylon fabric with the super-hydrophobic surface. As shown in fig. 1, micron-sized hydrophobic resin is adhered to the fiber surface of the superhydrophobic nylon fabric, and nanoparticles are coated in the resin. The low surface energy of the micro/nano coarse structure and the hydrophobic resin makes the nylon fabric which is originally hydrophilic to be super-hydrophobic.

Example 2

Hydrophobic organic silicon resin prepolymer (Sylgard 184A, Dow Corning) and curing agent (Sylgard184B, Dow Corning) thereof are dissolved in good solvent tetrahydrofuran, fluorine modified nano-silica (particle size 20nm-30nm) is added after complete dissolution, and dispersed for 5min at the rotating speed of 7000r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 25KHz, dropwise adding distilled water in 30 deg.C water bath, and completing dripping within 50min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 6% of hydrophobic organic silicon resin, 0.5% of curing agent, 50% of tetrahydrofuran, 6% of fluorine modified silicon dioxide and the balance of water.

Soaking the cleaned nylon fabric into the dispersed emulsion for 30min at the system temperature of 30 ℃, taking out the fabric, extruding and removing the redundant coating, drying and curing for 30min at the temperature of 60 ℃ to obtain the nylon fabric with the super-hydrophobic surface, wherein the surface contact angle is 161.3 degrees (the water drop volume is 10 microliters, and the measurement mode is the Laplace-Young mode) (figure 2).

Example 3

Dissolving hydrophobic fluorocarbon resin polyvinylidene fluoride (molecular weight of 100000) and polymethyl methacrylate (molecular weight of 30000) in good solvent tetrahydrofuran, completely dissolving, adding alkyl modified nano silicon dioxide (particle size of 50nm-70nm), and dispersing for 10min at the rotation speed of 4000r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 30KHz, dropwise adding distilled water in water bath at 30 deg.C, and completing dripping within 60min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 10% of hydrophobic fluorocarbon resin, 0.8% of adhesive resin polymethyl methacrylate, 60% of tetrahydrofuran, 3% of alkyl modified silicon dioxide and the balance of water.

Selecting an outer wall area of a building, repeatedly washing the building with detergent and clean water, and fully drying the building. And spraying the well-dispersed super-hydrophobic water-based paint on the surface of the outer wall at the ambient temperature, wherein the spraying angle is 90 degrees, the spraying pressure is 0.2MPa, the spraying distance is 15cm, and the building outer wall in the area has the super-hydrophobic surface after the coating is fully dried. After the exterior wall sample is coated, the surface contact angle is 159.5 degrees (the water drop volume is 10 microliter, and the measurement mode is Laplace-Young mode) (figure 3). The coating thickness can be increased through multiple spraying-drying processes, and the durability of the super-hydrophobic coating is enhanced.

Example 4

Dissolving hydrophobic fluorocarbon resin polyvinylidene fluoride (molecular weight of 140000) and polymethyl methacrylate (molecular weight of 30000) in good solvent acetone, adding nano titanium dioxide (particle size of 5nm-8nm) after completely dissolving, and dispersing for 10min at 6000r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 35KHz, dropwise adding distilled water in water bath at 30 deg.C, and finishing dripping within 100min to obtain uniformly dispersed emulsion. Fig. 4 is a photograph of an optical microscope of a coating emulsion in which the size of the resin droplets in the coating system is between a few microns and a dozen or so microns to facilitate the formation of micron-scale roughness structures upon subsequent curing. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 3% of hydrophobic fluorocarbon resin, 0.7% of polymethyl methacrylate, 50% of acetone, 5% of nano titanium dioxide and the balance of water.

Selecting an outer wall area of a building, repeatedly washing the building with detergent and clean water, and fully drying the building. And spraying the dispersed super-hydrophobic water-based paint on the surface of the outer wall at the ambient temperature, wherein the spraying angle is 90 degrees, the spraying pressure is 0.5MPa, the spraying distance is 15cm, and the building outer wall in the area has the super-hydrophobic surface after the paint is fully dried and cured. The coating thickness can be increased through multiple spraying-drying processes, and the durability of the super-hydrophobic coating is enhanced.

Example 5

Dissolving hydrophobic fluorinated modified epoxy resin (epoxy resin grafted and modified by hexafluorobutyl methacrylate, wherein the mass ratio of the epoxy resin to the hexafluorobutyl methacrylate is 6: 1) and a curing agent hexamethylene diisocyanate in a good solvent N, N-dimethylformamide thereof, adding nano alumina (with the particle size of 100nm-130nm) after completely dissolving, and dispersing for 5min at the rotating speed of 7000r/min by using a high-speed disperser to obtain a uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 40KHz, dropwise adding distilled water in water bath at 30 deg.C, and finishing dripping within 40min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 2.5% of hydrophobic fluorinated modified epoxy resin, 0.12% of hexamethylene diisocyanate, 20% of N, N-dimethylformamide, 2% of nano aluminum oxide and the balance of water.

Soaking the cleaned peach wood blocks in the dispersed emulsion at the system temperature of 40 ℃ for 50min, taking out the peach wood blocks, and drying at 110 ℃ for 60min to obtain the peach wood blocks with the super-hydrophobic surface.

Example 6

Dissolving hydrophobic fluorinated modified epoxy resin (epoxy resin grafted and modified by hexafluorobutyl methacrylate, wherein the mass ratio of the epoxy resin to the hexafluorobutyl methacrylate is 6: 1) and a curing agent hexamethylene diisocyanate thereof in good solvent acetone, adding alkyl modified nano silicon dioxide (with the particle size of 120nm-150nm) after complete dissolution, and dispersing for 15min at the rotating speed of 4000r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 40KHz, dropwise adding distilled water in 50 deg.C water bath, and completing dripping within 120min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 3% of hydrophobic fluorinated modified epoxy resin, 0.9% of hexamethylene diisocyanate, 30% of acetone, 5.5% of alkyl modified nano silicon dioxide and the balance of water.

Soaking the cleaned peach wood blocks into the dispersed emulsion at the system temperature of 50 ℃ for 30min, taking out the peach wood blocks, and drying and curing at 120 ℃ for 60min to obtain the peach wood blocks with the super-hydrophobic surface.

Example 7

Dissolving hydrophobic fluorinated modified polyurethane and butyl methacrylate (molecular weight 50000) in good solvent tetrahydrofuran, wherein the fluorinated modified polyurethane is prepared from FEVE type fluororesin ZY-1 (Xuzhou Zhongzhou fluorine chemistry Co., Ltd.) and hexamethylene diisocyanate in a weight ratio of 10: 1, adding fumed silica (with the particle size of 20nm-30nm) after the fumed silica is completely dissolved, and dispersing for 5min at the rotating speed of 5000r/min by using a high-speed disperser to obtain a uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 40KHz, dropwise adding distilled water in water bath at 30 deg.C, and finishing dripping within 40min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 1.5% of hydrophobic fluorinated modified polyurethane, 0.5% of butyl methacrylate, 60% of tetrahydrofuran, 4% of fumed silica and the balance of water.

Clean A4 paper is taken, and the dispersed super-hydrophobic water-based paint is sprayed on the paper at the ambient temperature, wherein the spraying angle is 90 degrees, the spraying pressure is 0.4MPa, and the spraying distance is 20 cm. And (3) drying the A4 paper at 40 ℃ for 120min, and after the coating is fully dried, the A4 paper has a super-hydrophobic surface. The coating thickness can be increased through multiple spraying-drying processes, and the durability of the super-hydrophobic coating is enhanced.

Example 8

Hydrophobic organic silicon resin prepolymer (Sylgard 184A, Dow Corning) and curing agent (Sylgard184B, Dow Corning) thereof are dissolved in good solvent tetrahydrofuran, fluorinated modified nano-silica (particle size is 40nm-50nm) is added after complete dissolution, and dispersed for 8min at the rotating speed of 3500r/min by using a high-speed disperser to obtain uniformly dispersed suspension. The resulting suspension was placed in a container, which was immersed in an ultrasonic water bath. Setting ultrasonic frequency at 30KHz, dropwise adding distilled water in water bath at 30 deg.C, and finishing dripping within 40min to obtain uniformly dispersed emulsion. The super-hydrophobic water-based paint comprises the following raw materials in percentage by mass: 12% of hydrophobic organic silicon resin, 0.9% of curing agent, 50% of tetrahydrofuran, 3% of fluorinated modified nano silicon dioxide and the balance of water.

Clean A4 paper is taken, and the dispersed super-hydrophobic water-based paint is sprayed on the paper at the ambient temperature, wherein the spraying angle is 90 degrees, the spraying pressure is 0.3MPa, and the spraying distance is 15 cm. And (3) drying the A4 paper for 60min at 40 ℃, and after the coating is fully dried and cured, the A4 paper has a super-hydrophobic surface. The coating thickness can be increased through multiple spraying-drying processes, and the durability of the super-hydrophobic coating is enhanced.

The invention is not the best known technology.

Claims

1. A water-based super-hydrophobic coating is characterized by comprising the following raw materials in percentage by mass: 1-20% of hydrophobic resin, 10-90% of good solvent of the hydrophobic resin, 0.01-1% of additive, 0.1-10% of nano-particles and the balance of water;

the additive is a curing agent or adhesive resin;

the hydrophobic resin is one or more of organic silicon resin, fluorocarbon resin, fluorinated modified epoxy resin and fluorinated modified polyurethane;

the good solvent of the hydrophobic resin is one or more of methanol, ethanol, isopropanol, tetrahydrofuran, acetone, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone;

the nano particles are one or more of fumed silica, nano titanium dioxide, nano alumina, fluorine modified nano silica and alkyl modified nano silica, and the particle size of the particles is 5nm-300 nm;

the adhesive resin is one or more of polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate and glyceryl polymethacrylate;

the curing agent is one or more of vinyl-terminated siloxane, organic polyisocyanate and amino resin;

step 1, dissolving hydrophobic resin and a curing agent in a good solvent according to the proportion to obtain a hydrophobic resin solution;

step 2, adding the additive and the nano particles into the hydrophobic resin solution obtained in the step 1, and dispersing for 1-30 min at a high speed by a high-speed disperser to obtain a uniformly mixed suspension;

step 3, placing the suspension obtained in the step 2 into a container, immersing the container into an ultrasonic water bath, ultrasonically dispersing, simultaneously dropwise adding distilled water into the suspension, and completing dropwise adding at a constant speed within 10-180 min to obtain an emulsion, namely the water-based super-hydrophobic coating;

in the step 2, the working rotating speed of the high-speed disperser is 2000r/min-8000 r/min;

2. The use of the water-based superhydrophobic coating of claim 1, comprising the steps of:

and (3) dip-coating or spray-coating the cleaned substrate with the emulsion obtained in the step (3), and drying and curing at 50-150 ℃ for 10-180 min to form the super-hydrophobic coating on the substrate.

3. The use of the water-based superhydrophobic coating of claim 2, wherein the substrate is a textile fabric, an exterior wall of a building, a wooden fixture, paper, or a metal.

4. The use of the water-based superhydrophobic coating according to claim 2, characterized in that when the dipping treatment is performed, the soaking time is 5min to 60 min; when the spraying treatment is carried out, the spraying angle is 60-90 degrees, the spraying distance is 10-35 cm, the spraying pressure is 0.1-0.6 MPa, and the substrate temperature is 20-100 ℃.