Bionic hydrophobic coating and its construction method on building exterior wall

Abstract

This invention relates to the field of coating production technology, specifically to a biomimetic hydrophobic coating and its application method on building exterior walls; the biomimetic hydrophobic coating is composed of the following components by weight percentage: 40-60 parts styrene-acrylic emulsion, 10-15 parts zinc stearate, 3-5 parts hydrophobic antibacterial agent, 3-6 parts pigment, 1-3 parts polyamide wax, 2-3 parts nano zinc oxide, 2-4 parts hydroxyethyl cellulose, 1-2 parts propylene glycol methyl ether acetate, 2-3 parts ultraviolet absorber, 0.8-1.5 parts dispersant, 0. 6-1 parts defoamer and 20-30 parts water; This invention uses dodecafluoroheptyl methacrylate, silane coupling monomer, glycidyl methacrylate and nano titanium dioxide as raw materials to finally obtain a hydrophobic antibacterial agent with excellent hydrophobicity and photocatalytic antibacterial properties; The prepared coating not only has excellent hydrophobic, self-cleaning and antibacterial properties, but also has high construction efficiency and stable coating quality. It is suitable for high-end residences, hospitals, schools and other scenarios with high requirements for wall protection and hygiene, and has broad market prospects.

Description

Technical Field

[0001] This invention relates to the field of coating production technology, specifically to a biomimetic hydrophobic coating and its application method on building exterior walls. Background Technology

[0002] Building exterior walls are exposed to the natural environment for extended periods, enduring sun and rain, pollution, and microbial buildup. This can easily lead to coating chalking, discoloration, staining, and even mold and algae growth, severely impacting the building's aesthetics and lifespan. While traditional coatings offer some protection, their hydrophobicity, stain resistance, and antibacterial properties are often unsatisfactory, requiring frequent cleaning and maintenance at high costs.

[0003] Inspired by the hydrophobic properties of lotus leaves, biomimetic hydrophobic coatings have become a research hotspot. These coatings achieve self-cleaning by constructing micro-nano rough structures and introducing low surface energy materials, causing water to bead up and roll off the surface, carrying away contaminants. However, many existing hydrophobic coatings have poor antibacterial properties and are complex and costly to produce. Based on the above, this invention provides a biomimetic hydrophobic coating and its application method on building exterior walls to solve the aforementioned technical problems! Summary of the Invention

[0004] This invention uses dodecafluoroheptyl methacrylate, silane coupling monomers, glycidyl methacrylate, and nano-titanium dioxide as raw materials to finally obtain a hydrophobic antibacterial agent with excellent hydrophobicity and photocatalytic antibacterial properties. The prepared coating not only has excellent hydrophobic, self-cleaning, and antibacterial properties, but also has high construction efficiency and stable coating quality. It is suitable for high-end residences, hospitals, schools, and other scenarios with high requirements for wall protection and hygiene, and has broad market prospects.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A biomimetic hydrophobic coating is composed of the following components in weight percentage: 40-60 parts styrene-acrylic emulsion, 10-15 parts zinc stearate, 3-5 parts hydrophobic antibacterial agent, 3-6 parts pigment, 1-3 parts polyamide wax, 2-3 parts nano zinc oxide, 2-4 parts hydroxyethyl cellulose, 1-2 parts propylene glycol methyl ether acetate, 2-3 parts ultraviolet absorber, 0.8-1.5 parts dispersant, 0.6-1 part defoamer, and 20-30 parts water.

[0007] Furthermore, the preparation method of the hydrophobic antibacterial agent includes the following steps:

[0008] Step 1: Mix dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate in a molar ratio of 5-10:2-4:1 and stir until homogeneous. Then, add a reaction promoter to the resulting mixture and disperse it evenly. Over 2-4 hours, slowly drop the resulting mixture into butyl acetate at a volume of 2-5 times its volume and a temperature of 75-85°C. After mixing, react at 75-85°C for 3-6 hours. After the reaction is complete, store the resulting modifier for later use.

[0009] The second step involves mixing the modifier with nano-titanium dioxide with an average particle size of 100-200 nm at a mass ratio of 1:0.8-1.2. Then, 10-20% by mass of silane coupling agent and 20-30% by mass of 85-90% ethanol aqueous solution are added. After mixing evenly, the mixture is ultrasonically reacted at 60-70℃ for 3-5 hours. After the reaction is complete, the product components are centrifuged, washed with ethanol, and vacuum dried in sequence to obtain the hydrophobic antibacterial agent.

[0010] Furthermore, the reaction promoter is selected from any one of azobisisobutyronitrile, benzoyl peroxide, and azobisisoheptanenitrile, and its amount is 0.8-1.2 wt% of the mixture.

[0011] Furthermore, the silane coupling agent is selected from either γ-aminopropyltriethoxysilane or γ-(2,3-epoxypropoxy)propyltrimethoxysilane.

[0012] Furthermore, the ultrasonic frequency during the ultrasonic response is 20-30kHz, and the ultrasonic power is 300-500W.

[0013] Furthermore, the pigment is selected from any one of aluminum tripolyphosphate, zinc yellow, iron oxide red, barium sulfate, and pearlescent powder.

[0014] Furthermore, the ultraviolet absorber is selected from any one of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, and 2-hydroxy-4-n-octyloxybenzophenone.

[0015] Furthermore, the dispersant is selected from any one of SN-5027 dispersant, SN-5034 dispersant, and SN-5040 dispersant.

[0016] Furthermore, the defoamer is selected from any one of BYK-141 defoamer, BYK024 defoamer, BYK085 defoamer, and TEGO-900 defoamer.

[0017] A method for applying a biomimetic hydrophobic coating to the exterior walls of a building includes the following steps:

[0018] Step 1: Clean the exterior wall base layer to ensure it is firm, flat, dry, clean, and free of oil, dust, and loose materials; repair cracks and holes, and reinforce the inside and outside corners and joints.

[0019] Step 2: Apply an alkali-resistant sealing primer evenly to the cleaned exterior wall base surface by brushing or rolling, and then allow it to dry.

[0020] Step 3: Put all raw materials into a high-speed disperser and disperse them at a speed of 800-1200 r / min until a uniform and fine slurry is formed; after standing for 10-20 minutes, store the resulting biomimetic hydrophobic coating for later use.

[0021] Step 4: Using an airless spraying device, evenly spray the prepared biomimetic hydrophobic coating onto the dry primer layer, and then cure it. The spraying pressure should be controlled at 15-20MPa, the spray gun nozzle should be 30-50cm away from the wall, and the spray gun should be moved vertically. Spray 1-2 coats, with an interval of at least 4 hours between the two coats.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention uses dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate as raw materials to prepare a modifier with both antibacterial and hydrophobic properties. Then, using this modifier in conjunction with a silane coupling agent, nano-titanium dioxide is modified. Finally, the silane coupling agent acts as a "bridge" to successfully bond the modifier to the surface of the nano-titanium dioxide, achieving dual functionalization of hydrophobic and antibacterial properties, and ultimately preparing a hydrophobic antibacterial agent. The introduction of the modifier significantly improves the hydrophobic and antibacterial properties of nano-titanium dioxide. Using the prepared hydrophobic antibacterial agent as a raw material for biomimetic hydrophobic coatings not only effectively improves its hydrophobic properties but also significantly enhances its antibacterial properties, effectively ensuring its quality and performance while also inhibiting the growth and reproduction of microorganisms on the surface of the biomimetic hydrophobic coating, effectively extending its service life.

[0024] The modifier prepared in this invention is essentially a fluorosilicone polymer with excellent hydrophobic and antibacterial properties. The prepared hydrophobic antibacterial agent uses nano-titanium dioxide as the "core" and the modifier as the "shell," with the fluorosilicone polymer and zinc stearate in the "shell" layer synergistically constructing a micro-nano hierarchical rough structure. This synergistic effect gives the coating excellent hydrophobic properties; water droplets easily roll off the surface of the biomimetic hydrophobic coating, effectively carrying away dust and contaminants, achieving a self-cleaning effect. Furthermore, the hydrophobic surface of the coating makes it difficult for mold spores and bacteria to adhere and remain, physically isolating the moisture and nutrient environment necessary for microbial survival.

[0025] The airless spraying method provided by this invention is highly efficient, produces uniform coatings, and has good adhesion. It is very suitable for large-area exterior wall projects, and is especially applicable to high-end residences, public buildings, hospitals, schools, and other occasions with extremely high requirements for exterior wall protection and hygiene. It has broad market application prospects. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] A biomimetic hydrophobic coating comprises the following components in weight percentage: 40 parts styrene-acrylic emulsion (Badfu RS-998A), 10 parts zinc stearate, 3 parts hydrophobic antibacterial agent, 3 parts aluminum tripolyphosphate, 1 part polyamide wax, 2 parts nano zinc oxide, 2 parts hydroxyethyl cellulose, 1 part propylene glycol methyl ether acetate, 2 parts 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 0.8 parts SN-5027 dispersant, 0.6 parts BYK-141 defoamer, and 20 parts water.

[0029] The preparation method of the hydrophobic antibacterial agent includes the following steps:

[0030] Step 1: Mix dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate in a molar ratio of 5:2:1 and stir until homogeneous. Then, add a reaction accelerator to the resulting mixture and disperse it evenly. Within 2 hours, slowly dropwise add the resulting mixture into butyl acetate at twice its volume and a temperature of 75°C. Mix well and react at 75°C for 6 hours. After the reaction is complete, store the resulting modifier for later use. The reaction accelerator used is azobisisobutyronitrile (AIBN), and its dosage is 0.8 wt% of the mixture.

[0031] The second step involves mixing the modifier with nano-titanium dioxide with an average particle size of 100 nm at a mass ratio of 1:0.8. Then, 10% by mass of γ-aminopropyltriethoxysilane and 20% by mass of 85% ethanol aqueous solution are added. After mixing evenly, the mixture is ultrasonically reacted at 60°C for 5 hours. After the reaction is complete, the product components are centrifuged, washed with ethanol, and vacuum dried sequentially to obtain the hydrophobic antibacterial agent. The ultrasonic frequency during the ultrasonic reaction is 20 kHz, and the ultrasonic power is 300 W.

[0032] A method for applying a biomimetic hydrophobic coating to the exterior walls of a building includes the following steps:

[0033] Step 1: Clean the exterior wall base layer to ensure it is firm, flat, dry, clean, and free of oil, dust, and loose materials; repair cracks and holes, and reinforce the inside and outside corners and joints.

[0034] Step 2: Apply an even coat of alkali-resistant sealing primer (purchased from Fenyangtang (Shanghai) Industrial Co., Ltd.) to the cleaned exterior wall base surface by brushing or rolling, and then allow it to dry.

[0035] Step 3: Put all raw materials into a high-speed disperser and disperse them at a speed of 800 r / min until a uniform and fine slurry is formed; after standing for 10 minutes, store the resulting biomimetic hydrophobic coating for later use.

[0036] Step 4: Using an airless spraying device, evenly spray the prepared biomimetic hydrophobic coating onto the dry primer layer, and then cure it. The spraying pressure should be controlled at 15MPa, the spray gun nozzle should be 30cm away from the wall, and the spray gun should be moved vertically. One coat should be sprayed, and the interval between two coats should be at least 4 hours.

[0037] Example 2

[0038] A biomimetic hydrophobic coating comprises the following components by weight percentage: 50 parts styrene-acrylic emulsion (Badfu RS-998A), 12 parts zinc stearate, 4 parts hydrophobic antibacterial agent, 5 parts zinc yellow, 2 parts polyamide wax, 3 parts nano zinc oxide, 3 parts hydroxyethyl cellulose, 2 parts propylene glycol methyl ether acetate, 3 parts 2,4-dihydroxybenzophenone, 1 part SN-5034 dispersant, 0.8 parts BYK024 defoamer, and 25 parts water.

[0039] The preparation method of the hydrophobic antibacterial agent includes the following steps:

[0040] Step 1: Mix dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate in a molar ratio of 8:3:1 and stir until homogeneous. Then, add a reaction accelerator to the resulting mixture and disperse it evenly. Within 3 hours, slowly dropwise add the resulting mixture into butyl acetate at 80°C and a volume of 4 times its volume. Mix well and react at 80°C for 5 hours. After the reaction is complete, store the resulting modifier for later use. The reaction accelerator used is benzoyl peroxide, and its amount is 1 wt% of the mixture.

[0041] The second step involves mixing the modifier with an equal mass of nano-titanium dioxide with an average particle size of 150 nm, then adding 15% by mass of silane coupling agent and 25% by mass of 90% ethanol aqueous solution. After mixing thoroughly, the mixture is ultrasonically reacted at 65°C for 4 hours. After the reaction is complete, the product components are centrifuged, washed with ethanol, and vacuum dried sequentially to obtain the hydrophobic antibacterial agent. The silane coupling agent used is γ-(2,3-epoxypropoxy)propyltrimethoxysilane. The ultrasonic frequency during the ultrasonic reaction is 25 kHz, and the ultrasonic power is 400 W.

[0042] A method for applying a biomimetic hydrophobic coating to the exterior walls of a building includes the following steps:

[0043] Step 1: Clean the exterior wall base layer to ensure it is firm, flat, dry, clean, and free of oil, dust, and loose materials; repair cracks and holes, and reinforce the inside and outside corners and joints.

[0044] Step 2: Apply an even coat of alkali-resistant sealing primer (purchased from Fenyangtang (Shanghai) Industrial Co., Ltd.) to the cleaned exterior wall base surface by brushing or rolling, and then allow it to dry.

[0045] Step 3: Put all raw materials into a high-speed disperser and disperse them at a speed of 1000 r / min until a uniform and fine slurry is formed; after standing for 15 minutes, store the obtained biomimetic hydrophobic coating for later use.

[0046] Step 4: Using an airless spraying device, evenly spray the prepared biomimetic hydrophobic coating onto the dry primer layer, and then cure it. The spraying pressure should be controlled at 20MPa, the spray gun nozzle should be 40cm away from the wall, and the spray gun should be moved vertically. Two coats should be applied, with an interval of at least 4 hours between the two coats.

[0047] Example 3

[0048] A biomimetic hydrophobic coating comprises the following components by weight percentage: 60 parts styrene-acrylic emulsion (Badfu RS-998A), 15 parts zinc stearate, 5 parts hydrophobic antibacterial agent, 6 parts iron oxide red, 3 parts polyamide wax, 3 parts nano zinc oxide, 4 parts hydroxyethyl cellulose, 2 parts propylene glycol methyl ether acetate, 3 parts 2-hydroxy-4-methoxybenzophenone, 1.5 parts SN-5040 dispersant, 1 part BYK085 defoamer, and 30 parts water.

[0049] The preparation method of the hydrophobic antibacterial agent includes the following steps:

[0050] Step 1: Mix dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate in a molar ratio of 10:4:1 and stir until homogeneous. Then, add a reaction accelerator to the resulting mixture and disperse it evenly. Within 4 hours, slowly dropwise add the resulting mixture into butyl acetate at 85°C and a volume of 5 times its volume. Mix well and react at 85°C for 3 hours. After the reaction is complete, store the resulting modifier for later use. The reaction accelerator is azobisisoheptanenitrile, and its amount is 1.2 wt% of the mixture.

[0051] The second step involves mixing the modifier with nano-titanium dioxide with an average particle size of 200 nm at a mass ratio of 1:1.2. Then, 20% by mass of the modifier and 30% by mass of a 90% ethanol aqueous solution are added. After mixing thoroughly, the mixture is ultrasonically reacted at 70°C for 3 hours. After the reaction is complete, the product components are centrifuged, washed with ethanol, and vacuum dried sequentially to obtain the hydrophobic antibacterial agent. The silane coupling agent used is γ-aminopropyltriethoxysilane. The ultrasonic frequency during the ultrasonic reaction is 30 kHz, and the ultrasonic power is 500 W.

[0052] A method for applying a biomimetic hydrophobic coating to the exterior walls of a building includes the following steps:

[0053] Step 1: Clean the exterior wall base layer to ensure it is firm, flat, dry, clean, and free of oil, dust, and loose materials; repair cracks and holes, and reinforce the inside and outside corners and joints.

[0054] Step 2: Apply an even coat of alkali-resistant sealing primer (purchased from Fenyangtang (Shanghai) Industrial Co., Ltd.) to the cleaned exterior wall base surface by brushing or rolling, and then allow it to dry.

[0055] Step 3: Put all raw materials into a high-speed disperser and disperse them at a speed of 1200 r / min until a uniform and fine slurry is formed; after standing for 20 minutes, store the obtained biomimetic hydrophobic coating for later use.

[0056] Step 4: Using an airless spraying device, evenly spray the prepared biomimetic hydrophobic coating onto the dry primer layer, and then cure it. The spraying pressure should be controlled at 20MPa, the spray gun nozzle should be 50cm away from the wall, and the spray gun should be moved vertically. Two coats should be applied, with an interval of at least 4 hours between the two coats.

[0057] Comparative Example: The difference from Example 1 is that nano-titanium dioxide (average particle size of 100nm) is used in this comparative example instead of an equal amount of hydrophobic antibacterial agent.

[0058] Performance testing: The relevant performance of the biomimetic hydrophobic coating samples provided in Examples 1-3 and the comparative examples were tested as follows:

[0059] 1. Hydrophobic properties: The contact angle of water on the coating surface is measured using a contact angle meter.

[0060] 2. Antibacterial properties: The antibacterial properties of each group of coating samples were tested in accordance with the standard GB / T 21866-2008 "Determination of antibacterial properties and antibacterial effects of antibacterial coatings (films)".

[0061] 3. Anti-mildew performance: Refer to GB / T 1741-2007 Test method for anti-mildew resistance of paint film, and incubate for 28 days under the conditions of 28-30℃ and humidity >85% to evaluate the anti-mildew level (0 is the best and 5 is the worst).

[0062] 4. Stain resistance: Refer to GB / T 9780-2013 Test method for stain resistance of architectural coatings, and test the rate of decrease in reflectance (the smaller the value, the better).

[0063] 5. Resistance to artificial aging: Refer to GB / T 1865-2009 Paints and varnishes - Artificial weathering and artificial radiation exposure, test the chalking and discoloration of the coating after 600 hours of aging.

[0064] The test data obtained above are recorded in the table below:

[0065]

[0066] Note: The water contact angle data in the table have been rounded to the nearest integer.

[0067] By comparing and analyzing the relevant data in the table, it can be seen that this invention uses dodecafluoroheptyl methacrylate, silane coupling monomers, and glycidyl methacrylate as raw materials, along with nano-titanium dioxide, to ultimately produce a hydrophobic antibacterial agent with both excellent hydrophobicity and photocatalytic antibacterial properties. The prepared coating not only possesses excellent hydrophobic, self-cleaning, and antibacterial properties, but is also suitable for high-end residences, hospitals, schools, and other scenarios with high requirements for wall protection and hygiene, and has broad market prospects. This indicates that the biomimetic hydrophobic coating and its application method on building exterior walls provided by this invention have a broader market prospect and are more suitable for promotion.

[0068] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0069] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A biomimetic hydrophobic coating, characterized in that, It is composed of the following components in parts by weight: 40-60 parts styrene-acrylic emulsion, 10-15 parts zinc stearate, 3-5 parts hydrophobic antibacterial agent, 3-6 parts pigment, 1-3 parts polyamide wax, 2-3 parts nano zinc oxide, 2-4 parts hydroxyethyl cellulose, 1-2 parts propylene glycol methyl ether acetate, 2-3 parts ultraviolet absorber, 0.8-1.5 parts dispersant, 0.6-1 part defoamer, and 20-30 parts water; The preparation method of the hydrophobic antibacterial agent includes the following steps: Step 1: Mix dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, and glycidyl methacrylate in a molar ratio of 5-10:2-4:1 and stir until homogeneous. Then, add a reaction promoter to the resulting mixture and disperse it evenly. Over 2-4 hours, slowly drop the resulting mixture into butyl acetate at a volume of 2-5 times its volume and a temperature of 75-85°C. After mixing, react at 75-85°C for 3-6 hours. After the reaction is complete, store the resulting modifier for later use. The second step involves mixing the modifier with nano-titanium dioxide with an average particle size of 100-200 nm at a mass ratio of 1:0.8-1.

2. Then, 10-20% by mass of silane coupling agent and 20-30% by mass of 85-90% ethanol aqueous solution are added. After mixing thoroughly, the mixture is ultrasonically reacted at 60-70℃ for 3-5 hours. After the reaction is complete, the product components are centrifuged, washed with ethanol, and vacuum dried sequentially to obtain the hydrophobic antibacterial agent. The reaction accelerator is selected from any one of azobisisobutyronitrile, benzoyl peroxide, and azobisisoheptanenitrile, and its amount is 0.8-1.2 wt% of the mixture; The ultrasonic frequency during the ultrasonic response is 20-30kHz, and the ultrasonic power is 300-500W.

2. The biomimetic hydrophobic coating according to claim 1, characterized in that: The silane coupling agent is selected from either γ-aminopropyltriethoxysilane or γ-(2,3-epoxypropoxy)propyltrimethoxysilane.

3. The biomimetic hydrophobic coating according to claim 1, characterized in that: The pigment is selected from any one of aluminum trihydrogen phosphate, zinc yellow, iron oxide red, barium sulfate, and pearlescent powder.

4. The biomimetic hydrophobic coating according to claim 1, characterized in that: The ultraviolet absorber is selected from any one of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, and 2-hydroxy-4-n-octyloxybenzophenone.

5. The biomimetic hydrophobic coating according to claim 1, characterized in that: The dispersant is selected from any one of SN-5027 dispersant, SN-5034 dispersant, and SN-5040 dispersant.

6. The biomimetic hydrophobic coating according to claim 1, characterized in that: The defoamer is selected from any one of BYK-141 defoamer, BYK024 defoamer, BYK085 defoamer, and TEGO-900 defoamer.

7. A method for applying the biomimetic hydrophobic coating according to claim 1 to the exterior wall of a building, characterized in that, Includes the following steps: Step 1: Clean the exterior wall base layer to ensure it is firm, flat, dry, clean, and free of oil, dust, and loose materials; repair cracks and holes, and reinforce the inside and outside corners and joints. Step 2: Apply an alkali-resistant sealing primer evenly to the cleaned exterior wall base surface by brushing or rolling, and then allow it to dry. Step 3: Put all raw materials into a high-speed disperser and disperse them at a speed of 800-1200 r / min until a uniform and fine slurry is formed; after standing for 10-20 minutes, store the resulting biomimetic hydrophobic coating for later use. Step 4: Using an airless spraying device, evenly spray the prepared biomimetic hydrophobic coating onto the dry primer layer, and then cure it. The spraying pressure should be controlled at 15-20MPa, the spray gun nozzle should be 30-50cm away from the wall, and the spray gun should be moved vertically. Spray 1-2 coats, with an interval of at least 4 hours between the two coats.

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