Abstract Polydimethylsiloxane (PDMS) modified polyurethane (PU)/Ag composite coating with super-hydrophobicity and low infrared emissivity was prepared via glass rod scraping method using nano-SiO2, PDMS modified PU, and flaky Ag powder as micro-nano structural modifier, adhesive, and functional pigment, respectively. The effects of particle size of flaky Ag powder, Ag powder addition, and the ratio of Ag powder and nano-SiO2 on the coating performance have been discussed. The results show that when the particle size of flaky Ag powder was 10 µm, and the content of Ag powder in the coating was 50 wt%, the coating had a dense surface structure and lowest infrared emissivity. The modification of coating with appropriate amount of nano-SiO2 led to clear mastoid micro-nano rough structures on the coating surface, so that the coating could achieve super-hydrophobic properties. When the ratio of Ag powder and nano-SiO2 in the coating was 6:4, the WCA of the coating reached 151°, the sliding angle reached 9°, and the coating had outstanding self-cleaning performance. At the same time, the super-hydrophobic PDMS modified PU/Ag composite coating had relatively low emissivity (0.709) and extremely low glossiness (4.0) properties.

中文翻译：

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一种具有超疏水性和低红外发射率的 PDMS 改性聚氨酯/银复合涂层

摘要 以纳米SiO2、PDMS改性PU、片状Ag粉为微纳米结构改性剂、粘合剂，通过玻璃棒刮削法制备了具有超疏水性和低红外发射率的聚二甲基硅氧烷(PDMS)改性聚氨酯(PU)/Ag复合涂层。和功能性颜料。讨论了片状Ag粉的粒径、Ag粉的添加量、Ag粉与纳米SiO2的配比对涂层性能的影响。结果表明，当片状银粉粒径为10 μm，涂层中银粉含量为50 wt%时，涂层表面结构致密，红外发射率最低。适量的纳米SiO2对涂层进行改性，在涂层表面形成清晰的乳突微纳米粗糙结构，从而使涂层具有超疏水性能。当涂层中Ag粉与纳米SiO2的比例为6:4时，涂层的WCA达到151°，滑动角达到9°，涂层具有优异的自洁性能。同时，超疏水 PDMS 改性 PU/Ag 复合涂层具有相对较低的发射率 (0.709) 和极低的光泽度 (4.0)。