海洋环境下使用的光学窗口常因海水等附着而影响其光学性能。从固体-液体界面理论入手,分析了光学窗口的表面能对海水附着特性的影响,开发了一种外场环境下可以实施的光学窗口表面憎水改性工艺。该工艺采用一种含有氟烃基硅烷的活性物质掺杂于SiO2溶胶中,通过涂擦和低温固化方式,在光学窗口表面形成纳米憎水膜,该憎水膜可使SiO2表面能由30 mJ/m2降至5 mJ/m2以下,水接触角由47°增加至105°以上。试验研究了改性后光学窗口的盐水接触角、光学透过率及耐候性,结果表明,用于改性的憎水膜海洋环境使用寿命大于6个月。通过定期对光学表面实施憎水改性保养可以显著减少海水附着。

Serving in the marine environment, the optical performance of optical windows is often affected by seawater adhesion. In this paper, the relation between the surface energy of optical windows and seawater adhesion properties is analyzed based on the solid-liquid interface theory. A process of surface hydrophobic modification of optical windows has been developed, which can be implemented in the external fields. Based on the process, hydrophobic nano-films are formed on optical window by means of wiping and low temperature curing SiO2 solution which is doped with active materials including fluoroalkysilane. Surface energy of optical windows treated with the hydrophobic nano-films falls from 30 mJ/m2 to less than 5 mJ/m2 and the water contact angle increases from 47° to 105° or more, which effectively reduces seawater adhesion. The optical, hydrophobia and weather resistance performance of optical windows after hydrophobic modification are tested. The results show that the hydrophobic nano-films can be used more than 6 months in marine environment. It is clear that seawater adhesion can be significantly reduced through regular surface hydrophobic modification.