Transparency and water resistance of a superhydrophobic acrylic surface prepared using THF/IPA etching-assisted SiO<inf>2</inf> NPs

Abstract

A transparent and water-resistant superhydrophobic acrylic surface was successfully fabricated via the use of tetrahydrofuran/isopropyl alcohol (THF/IPA) etching-assisted SiO2 nanoparticles (NPs). A coating solution was prepared by mixing methyltrichlorosilane (MTCS)-modified SiO2 nanoparticles in THF/IPA at different ratios to improve the superhydrophobicity and roughness of the acrylic surface. The acrylic was then dipped into the coating solution for 1 min under ambient air. Superhydrophobicity with a high water contact angle (>155°) and low sliding angle (<5°) was observed after modification of the acrylic surfaces. A sample prepared using a THF/IPA ratio of 50/50 showed a normalized transmittance of 88%, which was determined to be the optimum condition. Moreover, the water resistance of samples prepared using a THF/IPA ratio higher than 50/50 reached over 18,000 drops, which is a necessary requirement for transparent self-cleaning applications.