纳米SiO2@超支化PDMS复合超疏水涂层的制备与性能调控

超疏水涂层在实际应用中受化学腐蚀、刮擦磨损等外界环境的影响，易造成涂层老化、开裂甚至脱落，造成涂层失效。因此，针对这一问题，设计出具备耐候性的自修复超疏水表面：以超支化聚二甲基硅氧烷为柔性基底和低表面能物质，引入纳米二氧化硅构筑表面粗糙结构，制备超疏水涂层。当SiO₂粒径为50 nm、固含量为30wt%时，得到了接触角为154.87°的超疏水涂层。经过5次胶带剥离试验，涂层表现出良好的机械稳定性。经历10次温差循环试验和24 h紫外光照射后，涂层表面接触角仍大于150°，表明涂层具有良好的耐候性。涂层经过80℃、2 h的热处理可修复划痕，表明该涂层具有一定的自修复功能。同时，Tafel及Nyquist测试结果表明，对基底进行超疏水处理可显著提高防腐性能，并且该涂层具有明显的自清洁效果。综上所述，本文所制备的纳米SiO₂@超支化聚二甲基硅氧烷(PDMS)复合超疏水涂层具有自修复功能，为自修复超疏水涂层的开发提供了新的研究策略。

Construction and property regulation of nano-SiO2@hyperbranched PDMS composite superhydrophobic coating

In practical application, affected by chemical corrosion, scratch and wear and other external environment, superhydrophobic coating is easy to aging, cracking and even falling off, resulting in coating failure. Therefore, to solve this problem, a self-healing superhydrophobic surface with weather resistance was designed: Hyperbranched polydimethylsiloxane (PDMS) was used as a flexible substrate and low surface energy material, and nano-silica was introduced to construct the surface rough structure to prepare the superhydrophobic coating. When SiO₂ particle size is 50 nm and solid content is 30wt%, the superhydrophobic coating with contact angle of 154.87° is obtained. The coating shows good mechanical stability after 5 times of tape peeling test. After 10 temperature difference cycling tests and 24 h UV irradiation, the surface contact angle is still greater than 150°, indicating that the coating has good weather resistance. The scratches can be partially healed by heat treatment at 80℃ for 2 h, indicating that the coating has certain self-healing function. At the same time, Tafel and Nyquist test results indicates that superhydrophobic treatment can significantly improve the corrosion resistance of the substrate, and the coating has obvious self-cleaning effect as well. In conclusion, the nano-SiO₂@hyperbranched PDMS composite superhydrophobic coating prepared in this work has self-healing function, which provides a new research strategy for the development of self-healing superhydrophobic coating.