Poly(siloxane-urethane) for wind and sand erosion resistant high speed rail and aircraft skin and method of making
Patent Information
- Application Number
- CN202611133732.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-29
- Publication Date
- 2026-09-25
AI Technical Summary
[0005]本发明针对现有技术的不足，提供了一种耐风沙侵蚀的高铁和飞机蒙皮用含氟聚（硅氧烷-氨酯）及其制备方法，解决了用于户外恶劣环境聚（硅氧烷-氨酯）涂层易受到风沙侵蚀的问题
[0016]本发明选用成本较低的含氟二元醇与端氨基单体作为扩链剂，来提高材料的疏水性能与耐化学性能，并在二氧化硅纳米粒子的作用下构筑出了一种微纳结构，得到了一种高疏水性能的聚（硅氧烷-氨酯）材料。
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Figure CN122810355A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of polyurethane material preparation technology, specifically relating to a poly(siloxane-urethane) resistant to wind and sand erosion for high-speed rail and aircraft skin and its preparation method. Background Technology
[0002] Polyurethane is a polymer material prepared through a stepwise polymerization reaction. It is formed by the reaction of hydroxyl-terminated polymers with isocyanates to form urethane bonds. It is known as a universal polymer material and has advantages such as high flexibility, good wear resistance, and excellent molding and processing performance. This makes polyurethane widely used in many fields such as waterproof coatings in building engineering, skin of high-speed rail and aircraft, and anti-corrosion and anti-slip coatings for ships.
[0003] However, although polyurethane materials have excellent performance, their coatings used in outdoor tools are susceptible to wind and sand erosion and wear, which leads to a decline in material performance. In addition, they have relatively high requirements for raw materials, requiring high-purity terminal hydroxyl ethers and special isocyanates. These specific raw materials are more expensive than ordinary polyols and isocyanates, and the preparation equipment requires precise control of temperature and pressure to ensure full mixing of the two components, resulting in high overall production costs. This limits their application scenarios.
[0004] Ma Chunfeng et al. from South China University of Technology designed a polyurea that combines self-healing and mechanical properties, exhibiting a self-healing efficiency of up to 98% and excellent impact resistance at room temperature. Liu Weifeng et al. from South China University of Technology designed a lignin microcapsule-polyurea coating with good self-healing properties. By endowing the material with self-healing properties, they achieved long-term use of the material and reduced the material's cost to some extent, but did not fundamentally solve the problem of high material cost. Summary of the Invention
[0005] This invention addresses the shortcomings of existing technologies by providing a fluorinated poly(siloxane-urethane) coating for high-speed rail and aircraft skins resistant to wind and sand erosion, along with its preparation method. This solves the problem of susceptibility to wind and sand erosion in poly(siloxane-urethane) coatings used in harsh outdoor environments. The poly(siloxane-urethane) is prepared by introducing a fluorinated chain extender into the prepolymer of the poly(siloxane-urethane), followed by the introduction of p-phenylenediamine to further improve the material's hydrophobic and self-healing properties. The specific preparation method is as follows:
[0006] (1) The hydroxyl-terminated polydimethylsiloxane and polytetrahydrofuran, which were placed in a vacuum oven to remove water for 2 hours, were dissolved in N,N-dimethylformamide and transferred to a reaction flask with nitrogen gas. The system temperature was controlled at 80℃.
[0007] (2) Dissolve isocyanate in N,N-dimethylformamide and add it dropwise to the system in step (1) using a dropping funnel. Add catalyst and control the stirring speed to 120-170 r / min. Stir and mix to allow it to react for 2 h under a nitrogen atmosphere at 70°C.
[0008] The isocyanate is one of toluene diisocyanate, isophorone diisocyanate, or hexamethylene diisocyanate; the catalyst is dibutyltin dilaurate, and its addition amount is 0.3% of the mass of the polyol and the isocyanate.
[0009] (3) Dissolve the castor oil that has been placed in a vacuum oven to remove water for 2 hours in N,N-dimethylformamide and transfer it to the reaction flask in step (2) with nitrogen gas. Heat the system to 80°C, slowly add hexafluorobisphenol A, and continue to react under nitrogen atmosphere for 3 hours. Then cool the system to 40°C, slowly add p-phenylenediamine, and react for 1 hour.
[0010] The molar ratio of castor oil to hydroxyl-terminated polydimethylsiloxane and polytetrahydrofuran is 1:1.8:3, and the molar ratio of polyol (castor oil, hydroxyl-terminated polydimethylsiloxane, and polytetrahydrofuran) to isocyanate is 1:2.1. The chain extenders are hexafluorobisphenol A and p-phenylenediamine; the molar ratio of hexafluorobisphenol A to p-phenylenediamine is (0.5-2):1, and the molar ratio of the total chain extender to isocyanate is 0.9-1:2.
[0011] (4) Add silica nanoparticles to the system and stir evenly to obtain poly(siloxane-urethane); then pour the poly(siloxane-urethane) into a polytetrafluoroethylene mold and place it in a vacuum oven for defoaming treatment. Finally, place it in a forced-air oven to cure and form a poly(siloxane-urethane) coating for high-speed rail and aircraft skin that is resistant to wind and sand erosion. The amount of silica nanoparticles added is 10%-20% of the total mass of the system.
[0012] The specific process for preparing poly(siloxane-urethane) resistant to wind and sand erosion for high-speed rail and aircraft skins according to this invention is as follows:
[0013]
[0014] This invention reduces the surface energy of materials by introducing fluorine and silicon atoms, thereby improving their hydrophobicity and chemical resistance. A low-cost fluorine-containing monomer, hexafluorobisphenol A, is selected as a chain extender to introduce fluorine atoms. Simultaneously, p-phenylenediamine is used to introduce urea bonds to construct a hydrogen bond network, further enhancing the material's hydrophobicity and self-healing properties. Furthermore, silica nanoparticles are added to create micro / nano structures on the material surface, resulting in a poly(siloxane-urethane) coating that combines performance and longevity, demonstrating significant application value in harsh outdoor environments.
[0015] Beneficial effects:
[0016] This invention selects low-cost fluorinated diols and terminal amino monomers as chain extenders to improve the hydrophobicity and chemical resistance of the material, and constructs a micro-nano structure under the action of silica nanoparticles to obtain a poly(siloxane-urethane) material with high hydrophobic properties. Attached Figure Description
[0017] Figure 1 The infrared spectrum of the poly(siloxane-urethane) material prepared in Example 2 is shown.
[0018] Figure 2 Stress-strain diagram of the poly(siloxane-urethane) material prepared in Example 2
[0019] Figure 3 The bar chart shows the contact angles of the poly(siloxane-urethane) material prepared in Example 2 with water, tea, beverages, milk, and coffee.
[0020] Figure 4 The thermogravimetric curve of the poly(siloxane-urethane) material prepared in Example 2 is shown. Detailed Implementation
[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] Example 1
[0023] First, place the polyols (hydroxyl-terminated polydimethylsiloxane, polytetrahydrofuran ether diol, and castor oil) in a vacuum oven to remove water for 2 hours.
[0024] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and a stirring speed of 130 r / min. Dissolve 2.35 g of isophorone diisocyanate in 5 ml of N,N-dimethylformamide and add it dropwise to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate and dissolve it in 1 ml of N,N-dimethylformamide, then add 0.1 ml of the solution to the reaction flask and react for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask and react for 1 h. Heat the system to 80 °C, weigh 1.02 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0025] Example 2
[0026] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and the stirring speed at 130 r / min. Add 2.47 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80 °C, weigh 1.19 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0027] The structure of poly(siloxane-urethane) was analyzed using a Fourier transform infrared spectroscopy (NICOLET IS 10, USA). The FTIR spectra of the material were measured in attenuated total reflectance (ATR) mode. The scanning range was 4000–500 cm⁻¹.-1 The resolution is 4.0 cm. -1 A total of 32 scans were performed. The hydrophobicity of the material was tested using a contact angle meter. The material was cut into dumbbell strips and tensile tests were conducted using a universal tensile testing machine, with the tensile rate controlled at 20 mm / min. Thermogravimetric analysis of the material was performed in a N2 atmosphere at 10 °C / min using a simultaneous thermal analyzer (TG 209 F3, Netzsch, Germany).
[0028] like Figure 1 The infrared spectrum of the prepared poly(siloxane-urethane) shows that at 1500 cm⁻¹... -1 A benzene ring stretching vibration peak appears at 1250 cm⁻¹. -1 A stretching vibration peak of the CF bond appears, and it is at 2250 cm⁻¹. -1 The isocyanate peak disappears at 1730 cm⁻¹ -1 A C=O stretching vibration peak appears at 1100 cm⁻¹. -1 The appearance of a Si-O-Si stretching vibration peak at the point proves the successful preparation of poly(siloxane-urethane). Figure 2 The stress-strain curve of the material shows that the tensile strength reached 8.9 MPa and the strain reached 1022%, which is mainly due to the synergistic effect of the Si-O-Si flexible segments and the benzene ring rigid segments. Figure 3 The bar charts showing the contact angles of water, tea, beverages, milk, and coffee demonstrate that the material exhibits excellent hydrophobic properties for various common liquids. Figure 4 Thermogravimetric analysis of poly(siloxane-urethane) shows that the temperature at which the material has a 5% mass loss rate is 250℃ and the temperature at which the residual carbon rate is 30% is 399℃. This is mainly attributed to the extremely stable CF bond, which has a bond energy as high as 485kJ / mol. Breaking the bond requires a large amount of heat energy, thus endowing the material with excellent thermal stability.
[0029] Example 3
[0030] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and the stirring speed at 130 r / min. Add 2.62 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80 °C, weigh 1.34 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0031] Example 4
[0032] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and the stirring speed at 130 r / min. Add 2.75 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80 °C, weigh 1.53 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0033] Example 5
[0034] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70°C and the stirring speed at 130 r / min. Add 2.85 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80°C, weigh 1.7 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0035] Example 6
[0036] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and the stirring speed at 130 r / min. Add 2.47 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80 °C, weigh 1.19 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 1.2 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0037] Example 7
[0038] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70 °C and the stirring speed at 130 r / min. Add 1.6 g of hexamethylene diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate dissolved in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80 °C, weigh 1.19 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine and dissolve it in 5 ml of DMF, add it to the system and react for 1 h; finally add 0.8 g of silica nano-ions, mix them evenly, and after the reaction is complete, pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0039] Compare with Example 1
[0040] 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane were dissolved in 5 ml of N,N-dimethylformamide and transferred to a reaction flask purged with nitrogen. The reaction temperature was controlled at 70 °C and the stirring speed at 130 r / min. 2.30 g of isophorone diisocyanate was dissolved in 5 ml of N,N-dimethylformamide and added to the reaction flask. 0.1 g of dibutyltin dilaurate was dissolved in 1 ml of N,N-dimethylformamide, and 0.1 ml of this solution was added to the reaction flask and reacted for 2 h. 0.93 g of castor oil was dissolved in 5 ml of N,N-dimethylformamide and added to the reaction flask, and reacted for 1 h. The system was cooled to 40 °C, and 2.2 g of p-phenylenediamine was dissolved in 5 ml of N,N-dimethylformamide and slowly added to the reaction flask, reacting for 3 h. Finally, 0.8 g of [unspecified ingredient] was added. G of silica nano-ions were mixed evenly. After the reaction was completed, the product was poured into a polytetrafluoroethylene mold, placed in a vacuum oven to remove bubbles, and then placed in a forced-air oven to cure.
[0041] Compare with Example 2
[0042] 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane were dissolved in 5 ml of N,N-dimethylformamide and transferred to a reaction flask purged with nitrogen. The reaction temperature was controlled at 70 °C and the stirring speed at 130 r / min. 2.30 g of isophorone diisocyanate was dissolved in 5 ml of N,N-dimethylformamide and added to the reaction flask. 0.1 g of dibutyltin dilaurate was dissolved in 1 ml of N,N-dimethylformamide, and 0.1 ml of this solution was added to the reaction flask and reacted for 2 h. 0.93 g of castor oil was dissolved in 5 ml of N,N-dimethylformamide and added to the reaction flask, and reacted for 1 h. The system was heated to 80 °C, and 1.02 g of hexafluorobisphenol A was dissolved in 5 ml of N,N-dimethylformamide and slowly added to the reaction flask, reacting for 3 h. Finally, 0.8 g of [unspecified ingredient] was added. G of silica nano-ions were mixed evenly. After the reaction was completed, the product was poured into a polytetrafluoroethylene mold, placed in a vacuum oven to remove bubbles, and then placed in a forced-air oven to cure.
[0043] Compare with Example 3
[0044] Dissolve 3 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane in 5 ml of N,N-dimethylformamide, and transfer to a reaction flask purged with nitrogen. Maintain the reaction temperature at 70°C and the stirring speed at 130 r / min. Add 2.35 g of isophorone diisocyanate dissolved in 5 ml of N,N-dimethylformamide to the reaction flask. Weigh 0.1 g of dibutyltin dilaurate, dissolve it in 1 ml of N,N-dimethylformamide, and add 0.1 ml of the solution to the reaction flask. React for 2 h. Dissolve 0.93 g of castor oil in 5 ml of N,N-dimethylformamide and add it to the reaction flask. React for 1 h. Heat the system to 80°C, weigh 1.02 g of hexafluorobisphenol A, dissolve it in 5 ml of N,N-dimethylformamide, and slowly (without forming a column) add it to the reaction flask. React for 3 h. h; then cool the system to 40℃, take 2.2 g of p-phenylenediamine dissolved in 5 ml of DMF, add it to the system and react for 1 h; pour the product into a polytetrafluoroethylene mold, put it in a vacuum oven to remove bubbles, and then put it in a forced-air oven to cure.
[0045] Compare with Example 4
[0046] 4 g of polytetrahydrofuran and 1.5 g of hydroxyl-terminated polydimethylsiloxane were dissolved in 5 ml of N,N-dimethylformamide and transferred to a reaction flask purged with nitrogen. The reaction temperature was controlled at 70 °C and the stirring speed at 130 r / min. 2.35 g of isophorone diisocyanate was dissolved in 5 ml of N,N-dimethylformamide and added to the reaction flask. 0.1 g of dibutyltin dilaurate was dissolved in 1 ml of N,N-dimethylformamide, and 0.1 ml of this solution was added to the reaction flask and reacted for 2 h. The system was then heated to 80 °C, and 1.02 g of hexafluorobisphenol A was dissolved in 5 ml of N,N-dimethylformamide and added slowly (without forming a column) to the reaction flask. The reaction was allowed to proceed for 3 h. The system was then cooled to 40 °C, and 2.2 g of p-phenylenediamine was dissolved in 5 ml of DMF and added to the system and reacted for 1 h. Finally, 0.8 g of [unspecified substance] was added to the reaction flask. G of silica nano-ions were mixed evenly. After the reaction was completed, the product was poured into a polytetrafluoroethylene mold, placed in a vacuum oven to remove bubbles, and then placed in a forced-air oven to cure.
[0047] Table 1. Tensile strength and contact angle data of materials
[0048] Tensile strength Water contact angle Tea contact angle Milk contact angle Beverage contact angle Coffee contact angle Example 1 7.5MPa 103° 101° 90° 95° 89° Example 2 8.9MPa 108° 104° 98° 102° 97° Example 3 8.3MPa 113° 107° 102° 106° 100° Example 4 7.8MPa 115° 109° 105° 107° 103° Example 5 8.2MPa 119° 113° 109° 111° 106° Example 6 7.1MPa 110° 107° 100° 104° 99° Example 7 6.9MPa 120° 115° 109° 116° 107° Compare with Example 1 5.2MPa 91° 88° 75° 89° 72° Compare with Example 2 6.5MPa 112° 111° 104° 107° 100° Compare with Example 3 8.1MPa 94° 91° 82° 89° 79° Compare with Example 4 3.8MPa 117° 114° 102° 115° 99°
Claims
1. A method for preparing a poly(siloxane-urethane) resistant to wind and sand erosion, characterized in that: The preparation method steps are as follows: (1) After placing the polyol in a vacuum oven to remove water for 2 hours, first weigh the hydroxyl-terminated polydimethylsiloxane and polytetrahydrofuran and dissolve them in N,N-dimethylformamide, and transfer them to a three-necked flask; (2) Dissolve isocyanate in N,N-dimethylformamide and add it dropwise to the system of step (1) using a dropping funnel. Then add dibutyltin dilaurate, stir and mix and react under a nitrogen atmosphere. (3) Weigh castor oil and dissolve it in N,N-dimethylformamide, and add it to the system in step (2); first cool the system, add fluorinated chain extender, continue to react under nitrogen atmosphere, then lower the temperature and add the remaining chain extender to react fully; (4) Finally, add silica nanoparticles as nanofiller to the system and mix them evenly by stirring.
2. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that: In step (1), the polyols are hydroxyl-terminated polydimethylsiloxane, polytetrahydrofuran ether diol and castor oil, wherein the molar ratio of polydimethylsiloxane, polytetrahydrofuran ether diol and castor oil is 1.8:3:
1.
3. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that: In step (2), the isocyanate is either isophorone diisocyanate or hexamethylene diisocyanate.
4. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that: In step (2), the amount of dibutyltin dilaurate added is 0.3% of the total mass of the polyol and isocyanate participating in the reaction; the molar ratio of the total amount of polyol to isocyanate is 1:2.
1.
5. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that: In step (3), the fluorinated chain extender is hexafluorobisphenol A, and the remaining chain extenders are p-phenylenediamine. The molar ratio of hexafluorobisphenol A to p-phenylenediamine is 0.5-2:1; the molar ratio of the total amount of chain extender to isocyanate is 0.9-1:
2.
6. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that: In step (4), the amount of silica nanoparticles added is 10%-20% of the total mass of the system.
7. The method for preparing the wind-erosion resistant poly(siloxane-urethane) as described in claim 1, characterized in that, The process for preparing poly(siloxane-urethane) is as follows: 。 8. An application of a wind-erosion-resistant poly(siloxane-urethane) prepared by the method according to any one of claims 1-6, characterized in that, The poly(siloxane-urethane) is used to prepare coatings for high-speed rail and aircraft skins.