A polysiloxane silicone rubber waterproof coating and a preparation method thereof

Abstract

The application discloses a polysiloxane silicone rubber waterproof paint and a preparation method thereof, and relates to the technical field of paint preparation.The polysiloxane silicone rubber waterproof paint comprises the following raw materials in mass parts: component A: vinyl-containing perfluoropolyether-b-polysiloxane 50-60 parts; hydrophobic modified binder 10-15 parts; low-surface-energy modified silicon dioxide 6-8 parts; tetramethyltetravinylcyclotetrasiloxane 3-5 parts; component B: vinylphenyl silicone resin 10-20 parts; hydrogen-containing silicone oil 5-8 parts; platinum catalyst 0.2-0.4 parts; inhibitor 0.05-0.1 part.The polysiloxane silicone rubber waterproof paint prepared by the application is suitable for long-term protection of various substrates, has high adhesion, and especially has waterproofness and mechanical wear resistance.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, specifically to a polysiloxane silicone rubber waterproof coating and its preparation method. Background Technology

[0002] With the rapid development of infrastructure construction such as buildings and transportation, the performance requirements for waterproof coatings are increasing. Traditional waterproof coatings have limitations in terms of weather resistance, hydrophobicity, and durability, making it difficult to meet the long-term waterproofing needs in complex environments. Polyurethane coatings are susceptible to UV aging, leading to chalking and cracking, and have insufficient long-term weather resistance; acrylic coatings have limited hydrophobicity, with contact angles mostly below 90°, and poor resistance to chemical media. In recent years, polysiloxane silicone rubber waterproof coatings have received widespread attention due to their excellent high and low temperature resistance, weather resistance, and flexibility. However, existing products still suffer from problems such as high surface energy, poor hydrophobicity, and insufficient adhesion to the substrate. Although there have been studies on improving hydrophobicity by adding low surface energy substances and attempts to enhance adhesion using specific adhesives, single modification methods cannot simultaneously achieve superhydrophobicity and excellent mechanical properties, and compatibility issues between different modifying components can also affect the overall performance of the coating.

[0003] The strategy of introducing binders to improve coating adhesion has been favored by researchers due to its advantages such as simple process, low cost, and large-area preparation. It is usually combined with low surface energy nanoparticles and the coating can be prepared using simple spraying, dip coating, or brushing techniques. However, while introducing binders can significantly improve coating adhesion, their surface energy is usually high. Introducing binders also embeds low surface energy nanoparticles, leading to a sharp increase in the surface energy of the coating, resulting in poor superhydrophobic / superamphophobic properties and pressure resistance. Regarding weather resistance, researchers have found that chemically inert inorganic materials (such as inorganic binders) can help improve the weather resistance of coatings, but they also usually have high surface energy, so their introduction also leads to a sharp increase in surface energy. Therefore, there is an urgent need to develop a polysiloxane silicone rubber waterproof coating that combines superhydrophobicity, high bonding strength, and good durability to meet the demands of modern engineering construction for high-performance and long-life waterproof materials. Summary of the Invention

[0004] The purpose of this invention is to provide a polysiloxane silicone rubber waterproof coating and its preparation method, thereby solving the following technical problems: Existing waterproof coatings suffer from poor adhesion, poor abrasion resistance, and lack of durability.

[0005] The objective of this invention can be achieved through the following technical solutions: A polysiloxane silicone rubber waterproof coating comprises at least the following raw materials in parts by weight: Component A: Contains 50-60 parts of vinyl perfluoropolyether-b-polysiloxane; 10-15 parts of hydrophobic modified binder; 6-8 parts of low surface energy modified silica; and 3-5 parts of tetramethyltetravinylcyclotetrasiloxane. Component B: 10-20 parts vinyl phenyl silicone resin; 5-8 parts hydrogen-containing silicone oil; 0.2-0.4 parts platinum catalyst; 0.05-0.1 parts inhibitor.

[0006] As a further aspect of the present invention: the molar ratio of hydrogen content in the hydrogen-containing silicone oil to vinyl content in component A is 1.0-1.5:1.

[0007] As a further aspect of the present invention: the preparation method of the hydrophobic modified adhesive: Diaminopropyl-terminated polydimethylsiloxane and isoflurane diisocyanate were added to tetrahydrofuran to obtain isocyanate-terminated polysiloxane. 2-Amino-4-hydroxy-6-methylpyrimidine was dissolved in dimethyl sulfoxide and added to the isocyanate-terminated polysiloxane to obtain a hydrophobically modified adhesive.

[0008] As a further aspect of the present invention, the mass ratio of the diaminopropyl-terminated polydimethylsiloxane to the isoflurane diisocyanate is 15-20:1.

[0009] As a further aspect of the present invention, the mass ratio of the 2-amino-4-hydroxy-6-methylpyrimidine to the isocyanate-terminated polysiloxane is 1:15-25.

[0010] As a further aspect of the present invention, the method for preparing the low surface energy modified silica includes the following steps: Silica nanoparticles were dispersed in a mixed solvent of ethanol, ammonia and water, and tetraethyl orthosilicate and perfluorodecyltriethoxysilane were added to obtain low surface energy modified silica.

[0011] As a further aspect of the present invention: the ammonia water is 25wt% concentrated ammonia water, the mass ratio of the ethanol, the ammonia water and the water is 85-92:3-8:5-10, and the mass ratio of the silica nanoparticles, the tetraethyl orthosilicate and the perfluorodecyltriethoxysilane is 1:0.8-1.5:0.3-0.8.

[0012] As a further aspect of the present invention: the platinum catalyst is one or more of Karstedt platinum catalyst or chloroplatinic acid-olefin complex, and the inhibitor is one or more of ethynylcyclohexanol or diethyl maleate.

[0013] A method for preparing a polysiloxane silicone rubber waterproof coating includes at least the following preparation steps: Mix vinyl perfluoropolyether-b-polysiloxane and tetramethyltetravinylcyclotetrasiloxane, add low surface energy modified silica, grind and disperse to a particle size ≤5μm, then add hydrophobic modified binder, stir and vacuum degas to obtain component A premix; Vinylphenyl silicone resin and hydrogen-containing silicone oil were mixed evenly, platinum catalyst and inhibitor were added, the mixture was stirred and vacuum degassed to obtain component B premix. The premix of component A and component B are mixed at a mass ratio of 9-13:1 to obtain a polysiloxane silicone rubber waterproof coating.

[0014] The beneficial effects of this invention are: This invention uses a vinyl-containing perfluoropolyether-b-polysiloxane block copolymer as the matrix resin to achieve chemical bonding between fluorine elements and siloxane segments. This is combined with low-surface-energy modified silica to construct a micro / nano composite hydrophobic structure. A hydrophobic modified binder is added to enhance interfacial adhesion, ultimately forming a high-performance curing waterproof system. The hydrophobic modified binder acts as a "molecular bridge," with its polysiloxane segments compatible with the block copolymer. The 2-amino-4-hydroxy-6-methylpyrimidine groups form hydrogen bonds with the hydroxyl groups on the silica surface, reducing nanoparticle aggregation and improving system uniformity. The perfluoropolyether segments and the perfluorinated groups of the modified silica interact through van der Waals forces, forming a continuous low-surface-energy network, thus reducing the overall surface energy and significantly improving the coating's waterproofness. The flexible siloxane segments of the block copolymer and the hydrogen bond network of the hydrophobic modified binder jointly endow the coating with dual "elastic-self-healing" properties, enhancing the mechanical wear resistance of the waterproof coating. The nano-reinforcing effect of modified silica synergistically works with the cross-linking network, enabling the coating to possess both high tensile strength and high elongation at break, breaking through the bottleneck of traditional waterproof materials being "strong but not tough." The waterproof coating prepared by the polysiloxane silicone rubber waterproof coating provided by this invention exhibits excellent resistance to ultraviolet rays, ozone, corrosion, and high and low temperatures. Furthermore, the coating possesses good elasticity, adapting to minor deformations and thermal expansion and contraction of the substrate, making it less prone to cracking. It also exhibits high adhesion strength to various substrates (concrete, metal, ceramics, glass, and plastics).

[0015] In this invention, the hydrophobic modified binder added to the base of the anti-corrosion coating is a 2-amino-4-hydroxy-6-methylpyrimidine-terminated polysiloxane. The multiple hydrogen bonds between the 2-amino-4-hydroxy-6-methylpyrimidine groups enhance the interaction between polymer chains, thereby affecting the polymer's density, orderliness, and overall hydrophobic properties. The 2-amino-4-hydroxy-6-methylpyrimidine groups form a quadruple hydrogen bond network, significantly improving adhesion to substrates such as concrete. The polysiloxane segments of the polysiloxane block copolymer in the coating maintain a low surface energy at the interface, while the polar groups of 2-amino-4-hydroxy-6-methylpyrimidine form hydrogen bonds with the hydroxyl groups of the substrate, resolving the contradiction of insufficient adhesion in traditional low surface energy materials.

[0016] The silica nanofiller added in this invention is fluorinated with perfluorodecyl polysiloxane. The pyrimidine rings (—N=C—NH—) in the adhesive form hydrogen bonds with the silanol groups (Si—OH) on the silica surface, resulting in uniform dispersion of the nanoparticles and preventing agglomeration. The nanoparticles are uniformly dispersed in the silicone rubber matrix, acting as physical crosslinking points to improve coating hardness while avoiding increased brittleness caused by agglomeration. The synergistic effect of the perfluoropolyether segments in the vinyl-perfluoropolyether-b-polysiloxane block copolymer and the low surface energy modified silica endows the coating with extremely low surface energy and hydrophobic properties similar to the "lotus effect," effectively preventing liquid water penetration and providing excellent waterproof performance. Detailed Implementation

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1: The preparation method of the hydrophobic modified adhesive includes the following steps: First, 18g of diaminopropyl-terminated polydimethylsiloxane (PDMS) was added to a three-necked flask, and nitrogen gas was introduced for 10 minutes. 1.33g of isoflurane diisocyanate (IPDI) was dissolved in 20ml of tetrahydrofuran (THF) and slowly added dropwise to the flask. The reaction was carried out at room temperature for 5 hours, during which nitrogen gas was continuously used to prevent water in the air from reacting with the isocyanate groups. After the reaction was completed, the mixture was cooled to room temperature to obtain isocyanate-terminated polysiloxane.

[0019] 0.77 g of 2-amino-4-hydroxy-6-methylpyrimidine (UPy) was dissolved in 5 ml of dimethyl sulfoxide (DMSO), heated to 100 °C, and after complete dissolution, cooled to room temperature and added to the above isocyanate-terminated polysiloxane. The mixture was stirred at room temperature for 4 h, and after the reaction was completed, cooled to room temperature to obtain the hydrophobic modified adhesive.

[0020] Example 2: The preparation method of low surface energy modified silica includes the following steps: 10g of silica nanoparticles were mechanically stirred and ultrasonically dispersed in a mixed solvent consisting of 85g of ethanol, 5g of 25wt% concentrated ammonia, and 10g of water. Then, 12g of tetraethyl orthosilicate (TEOS) and 5g of perfluorodecyltriethoxysilane (PFDTES) were added, and the mixture was stirred for 2 hours to obtain a nanoparticle suspension. The ethanol in the suspension was then replaced three times by centrifugation with butyl acetate. After drying, low surface energy modified silica was obtained.

[0021] Example 3: The preparation method of vinyl-containing perfluoropolyether-b-polysiloxane includes the following steps: 17.76 g of octamethylcyclotetrasiloxane (D4), 3.44 g of tetramethyltetravinylcyclotetrasiloxane (D4Vi), and 20 mL of N,N-dimethylformamide (DMF) were added sequentially to a 100 mL reaction flask. The flask was evacuated and purged with nitrogen. Then, 6.2 mL of potassium tert-butoxide solution with a concentration of 1.0 mol / L was added. The mixture was stirred at room temperature for 30 min, heated to 70 °C, and reacted for 7 h. The reaction was stopped and cooled. 20 mL of ethanol was added for end-capping treatment. The mixture was washed with water, separated, and the solvent was removed under reduced pressure to obtain polyvinyl polysiloxanes in the chain. 15g of the prepared polyvinyl polysiloxane and 3.33g of perfluoropolyether siloxane were added to a dry reaction flask, along with 0.5g of catalyst TPFPB. The mixture was heated to 70°C and reacted for 8 hours. After the reaction was completed, 20mL of m-difluorotoluene and 20mL of methanol were added. The lower layer product was separated, and the solvent m-difluorotoluene was evaporated to obtain vinyl perfluoropolyether-b-polysiloxane.

[0022] Example 4: A method for preparing a polysiloxane silicone rubber waterproof coating includes the following steps: 55 parts by weight of the vinyl-containing perfluoropolyether-b-polysiloxane prepared in Example 3 and 4 parts by weight of tetramethyltetravinylcyclotetrasiloxane were added to a reaction vessel and stirred at 60°C for 30 minutes. 7 parts by weight of the low surface energy modified silica prepared in Example 2 were added to a high-speed disperser (2000 rpm) and dispersed for 1 hour. Then, 12 parts by weight of the hydrophobic modified binder prepared in Example 1 were slowly added. The mixture was heated to 80°C and stirred for 2 hours. Vacuum degassing was performed at -0.09 MPa to obtain component A premix. 15 parts by weight of vinylphenyl silicone resin and 6.5 parts by weight of hydrogen-containing silicone oil with a hydrogen content of 0.8 wt% were added to a dry stirred tank. Under nitrogen protection, the mixture was stirred at low speed until completely homogeneous. 0.3 parts by weight of Karstedt platinum catalyst and 0.08 parts by weight of inhibitor ethynylcyclohexanol were slowly added. The mixture was stirred at low speed for 2 hours until homogeneous. Vacuum degassing was performed at -0.09 MPa to obtain the premix of component B. The above-mentioned component A premix and component B premix are mixed at a mass ratio of 10:1 and stirred at high speed for 15 minutes to obtain a polysiloxane silicone rubber waterproof coating.

[0023] Example 5: A method for preparing a polysiloxane silicone rubber waterproof coating includes the following steps: 50 parts by weight of the vinyl-containing perfluoropolyether-b-polysiloxane prepared in Example 3 and 3 parts by weight of tetramethyltetravinylcyclotetrasiloxane were added to a reaction vessel and stirred at 60°C for 30 minutes. 6 parts by weight of the low surface energy modified silica prepared in Example 2 were added to a high-speed disperser (2000 rpm) and dispersed for 1 hour. Then, 10 parts by weight of the hydrophobic modified binder prepared in Example 1 were slowly added. The mixture was heated to 80°C and stirred for 2 hours. Vacuum degassing was performed at -0.09 MPa to obtain component A premix. Ten parts by weight of vinylphenyl silicone resin and five parts by weight of hydrogen-containing silicone oil with a hydrogen content of 0.5 wt% were added to a dry stirred tank. Under nitrogen protection, the mixture was stirred at low speed until completely homogeneous. Then, 0.2 parts by weight of Karstedt platinum catalyst and 0.05 parts by weight of inhibitor ethynylcyclohexanol were slowly added. The mixture was stirred at low speed for 2 hours until homogeneous. The mixture was then degassed under vacuum at -0.09 MPa to obtain the premix of component B. The above-mentioned component A premix and component B premix are mixed at a mass ratio of 10:1 and stirred at high speed for 15 minutes to obtain a polysiloxane silicone rubber waterproof coating.

[0024] Example 6 A method for preparing a polysiloxane silicone rubber waterproof coating includes the following steps: 60 parts by weight of the vinyl-containing perfluoropolyether-b-polysiloxane prepared in Example 3 and 5 parts by weight of tetramethyltetravinylcyclotetrasiloxane were added to a reaction vessel and stirred at 60°C for 30 minutes. 8 parts by weight of the low surface energy modified silica prepared in Example 2 were added to a high-speed disperser (2000 rpm) and dispersed for 1 hour. Then, 15 parts by weight of the hydrophobic modified binder prepared in Example 1 were slowly added. The mixture was heated to 80°C and stirred for 2 hours. Vacuum degassing was performed at -0.09 MPa to obtain component A premix. 20 parts by weight of vinylphenyl silicone resin and 8 parts by weight of hydrogen-containing silicone oil with a hydrogen content of 1.2 wt% were added to a dry stirred tank. Under nitrogen protection, the mixture was stirred at low speed until completely homogeneous. 0.4 parts by weight of Karstedt platinum catalyst and 0.1 parts by weight of inhibitor ethynylcyclohexanol were slowly added. The mixture was stirred at low speed for 2 hours until homogeneous. Vacuum degassing was performed at -0.09 MPa to obtain the premix of component B. The above-mentioned component A premix and component B premix are mixed at a mass ratio of 12:1 and stirred at high speed for 15 minutes to obtain a polysiloxane silicone rubber waterproof coating.

[0025] Compared with Example 4, Comparative Example 1 only replaced the hydrophobic modified binder prepared in Example 1 in Example 4 with the diaminopropyl-terminated polydimethylsiloxane in Example 1. The remaining components and preparation methods were completely the same as those in Example 4.

[0026] Compared with Example 4, Comparative Example 2 only replaced the low surface energy modified silica prepared in Example 2 with the unmodified nano silica in Example 2. The other components and preparation methods were completely the same as those in Example 4.

[0027] Compared with Example 4, Comparative Example 3 replaced the vinyl perfluoropolyether-b-polysiloxane-containing material prepared in Example 3 with 22.5 parts by mass of physically blended perfluoropolyether (PFPE) and 22.5 parts by mass of terminal vinyl polydimethylsiloxane (Vi-PDMS). The remaining components and preparation methods were completely consistent with those of Example 4.

[0028] Performance testing The polysiloxane silicone rubber waterproof coatings prepared in Examples 4-6 and Comparative Examples 1-3 were sprayed onto C30 concrete and cured at 25°C for 7 days. The coating thickness after curing was controlled at 150-200 μm to obtain the polysiloxane silicone rubber waterproof coating. Performance tests were then performed. Shore hardness test: The test was conducted according to GB / T2411-2008 standard. The testing instrument used was a Shore hardness tester model A manufactured by Mitutoyo Measuring Instruments of Japan. The sample was placed on a horizontal base, and the Shore hardness tester was held vertically. Then, it was pressed onto the sample without impact. The test position should be at least 9 mm away from the edge of the sample, and the pressure base near the probe should be in close contact with the sample during the test. The test results are shown in Table 1. Adhesion test: The coating adhesion test was conducted according to ASTM D3359. Two approximately 40mm long cut lines were made on the coating using a scalpel, with the included angle between the two lines between 30° and 40°, and the cut lines should be exposed above the substrate. 3M adhesive tape was then applied to the cut and quickly pulled off. The condition of the cut was then observed; the test results are shown in Table 1. Impact resistance test: The test was conducted according to the national standard "Determination of Impact Resistance of Paint Films" (GB / T1732-1993). A tinplate sheet coated with paint was placed flat on the test plate with the painted surface facing upwards. The weight was slid to the testing height and fixed. The control button was pressed, and the weight struck the test plate, creating a circular indentation. The paint film was observed for cracks, wrinkles, and peeling. The test was repeated three times; the results are shown in Table 1. Tensile mechanical property test: The sample was cut into a rectangular shape (2×8×40mm) and then placed on the test table for tensile testing until the sample broke (clamp speed was 5.0±0.2 mm / s); the test results are shown in Table 1; Table 1: Statistical Table of Waterproof Coating Performance Test Data for Examples 4-7 and Comparative Examples 2-6

[0029] As shown in Table 1, the waterproof coating obtained by the polysiloxane silicone rubber waterproof coating prepared in this invention has excellent mechanical properties and adhesion. In Comparative Example 1, no hydrophobic modified binder was added, resulting in a significant decrease in adhesion. In Comparative Example 2, the unmodified silica was prone to agglomeration. In Comparative Example 3, the fluorosilicone resin did not form blocks, leading to phase separation.

[0030] Water resistance test: Refer to GB / 1733-79 Test method for water resistance of paint film. Immerse 2 / 3 of the length of the coating test panel sealed with a mixture of paraffin and rosin into deionized water at a temperature of 23±2℃ and observe for whitening, loss of gloss, bubbles, etc.; the test results are shown in Table 2; UV aging resistance test: The coating was placed under a UV lamp with a wavelength of 365nm for 500 hours, and the tensile strength was tested; the test results are shown in Table 2; Solution immersion resistance test: The coating was immersed in 3.5wt% NaCl solution for 720 hours, and the presence of whitening, loss of gloss, bubbles, etc. was observed; the test results are shown in Table 2. Long-term stability test: The sample was tilted horizontally at about 4.5°, and the dynamic process of water droplets rolling on the sample after 18 months of indoor storage was recorded. Maintaining hydrophobicity (contact angle >150°) was considered passing; the test results are shown in Table 2. Table 2: Statistical Table of Waterproof Coating Performance Test Data for Examples 4-6 and Comparative Examples 1-3

[0031] As shown in Table 2, the waterproof coating obtained by the polysiloxane silicone rubber waterproof coating prepared in this invention has good water resistance, salt spray resistance and durability.

[0032] Pressure resistance test: High-pressure water jet impact test. The coating was placed on a platform tilted at 45°, with a distance of 20cm between the coating and the water outlet, and then continuously impacted with a 50kPa high-pressure water jet. After 30 minutes, the CA and SA of the coating were measured; the test results are shown in Table 3; Mechanical stability test: linear reciprocating friction test. The coated surface was placed face down on sandpaper (1000 grit), and then rubbed horizontally along the sandpaper under a pressure of 2.3 kPa (40 cm per cycle). After 1000 cycles, the CA and SA of the coating were measured; the test results are shown in Table 3. Table 3: Statistical Table of Pressure Resistance and Mechanical Stability Test Data for Examples 4-6 and Comparative Examples 1-3

[0033] As shown in Table 3, the waterproof coating obtained by the polysiloxane silicone rubber waterproof coating prepared in this invention has good pressure resistance and mechanical stability. In Comparative Example 1, no hydrophobic modified binder was added, resulting in weak interfacial bonding within the coating. In Comparative Example 2, the silica was not modified, and the surface hydrophilically adsorbed water molecules. In Comparative Example 3, the fluorosilicone resin did not form blocks, and phase separation formed defect channels, allowing water to directly impact the substrate.

[0034] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A polysiloxane silicone rubber waterproof coating, characterized in that, It shall include at least the following parts by weight of raw materials: Component A: Contains 50-60 parts of vinyl perfluoropolyether-b-polysiloxane; 10-15 parts of hydrophobic modified binder; 6-8 parts of low surface energy modified silica; and 3-5 parts of tetramethyltetravinylcyclotetrasiloxane. Component B: 10-20 parts vinyl phenyl silicone resin; 5-8 parts hydrogen-containing silicone oil; 0.2-0.4 parts platinum catalyst; 0.05-0.1 parts inhibitor; The mass ratio of component A to component B is 9-13:1; The molar ratio of hydrogen content in the hydrogen-containing silicone oil to vinyl content in component A is 1.0-1.5:1; The preparation method of the hydrophobic modified adhesive: Diaminopropyl-terminated polydimethylsiloxane and isoflurane diisocyanate were added to tetrahydrofuran to obtain isocyanate-terminated polysiloxane. 2-Amino-4-hydroxy-6-methylpyrimidine was dissolved in dimethyl sulfoxide and added to the isocyanate-terminated polysiloxane to obtain a hydrophobic modified adhesive. The preparation method of the low surface energy modified silica includes the following steps: Silica nanoparticles were dispersed in a mixed solvent of ethanol, ammonia and water, and tetraethyl orthosilicate and perfluorodecyltriethoxysilane were added to obtain low surface energy modified silica. The preparation method of the vinyl-containing perfluoropolyether-b-polysiloxane includes the following steps: 17.76 g of octamethylcyclotetrasiloxane, 3.44 g of tetramethyltetravinylcyclotetrasiloxane, and 20 mL of N,N-dimethylformamide were added sequentially to a 100 mL reaction flask. The flask was evacuated and purged with nitrogen. Then, 6.2 mL of potassium tert-butoxide solution with a concentration of 1.0 mol / L was added. The mixture was stirred at room temperature for 30 min, heated to 70 °C, and reacted for 7 h. The reaction was stopped and cooled. 20 mL of ethanol was added for end-capping treatment. The mixture was washed with water, separated, and the solvent was removed under reduced pressure to obtain polyvinyl polysiloxane in the chain. 15g of the polyvinyl polysiloxane and 3.33g of perfluoropolyether siloxane were added to a dry reaction flask, along with 0.5g of catalyst TPFPB. The mixture was heated to 70°C and reacted for 8 hours. After the reaction was completed, 20mL of m-difluorotoluene and 20mL of methanol were added. The lower layer product was separated, and the solvent was evaporated to obtain vinyl perfluoropolyether-b-polysiloxane.

2. The polysiloxane silicone rubber waterproof coating according to claim 1, characterized in that, The mass ratio of the diaminopropyl-terminated polydimethylsiloxane to the isoflurane diisocyanate is 15-20:

1.

3. The polysiloxane silicone rubber waterproof coating according to claim 1, characterized in that, The mass ratio of the 2-amino-4-hydroxy-6-methylpyrimidine to the isocyanate-terminated polysiloxane is 1:15-25.

4. The polysiloxane silicone rubber waterproof coating according to claim 1, characterized in that, The ammonia solution is a 25wt% concentrated ammonia solution, and the mass ratio of the ethanol, the ammonia solution, and the water is 85-92:3-8:5-10. The mass ratio of the silica nanoparticles, the tetraethyl orthosilicate, and the perfluorodecyltriethoxysilane is 1:0.8-1.5:0.3-0.

8.

5. The polysiloxane silicone rubber waterproof coating according to claim 1, characterized in that, The platinum catalyst is one or more of Karstedt platinum catalyst or chloroplatinic acid-olefin complex, and the inhibitor is one or more of ethynylcyclohexanol or diethyl maleate.

6. A method for preparing a polysiloxane silicone rubber waterproof coating according to any one of claims 1-5, characterized in that, It includes at least the following preparation steps: Mix vinyl perfluoropolyether-b-polysiloxane and tetramethyltetravinylcyclotetrasiloxane, add low surface energy modified silica, grind and disperse to a particle size ≤5μm, then add hydrophobic modified binder, stir and vacuum degas to obtain component A premix; Vinylphenyl silicone resin and hydrogen-containing silicone oil were mixed evenly, platinum catalyst and inhibitor were added, the mixture was stirred and vacuum degassed to obtain component B premix. The premix of component A and component B are mixed to obtain a polysiloxane silicone rubber waterproof coating.

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