Superhydrophobic coating of a modified calcium sulfate whiskers@SiO2-F/TPU for anti-icing applications

Abstract

Superhydrophobic materials have been explored extensively on account of their unique properties such as self-cleaning and anti-icing. However, most of materials that are used to prepare superhydrophobic coatings tend to be costly, and the coating durability is limited. Here, we used laboratory-produced low-cost calcium sulfate whiskers modified with sodium hexametaphosphate. The modified particles are further loaded with silica, produced by the hydrolysis of ethyl orthosilicate, on the surface. Finally, superhydrophobic coatings are prepared by surface modifying the composite particles with 1H,1H,2H,2H-perfluorodecyltrimethoxysilane and dispersing them into thermoplastic polyurethanes using N,N-dimethylformamide as a solvent. The coating exhibits excellent hydrophobicity with a contact angle of 159 ± 2° and a rolling angle of 7 ± 1°. These properties are attributed to the multi-scale structures constructed by the composite particles. Meanwhile, it also possesses good chemical stability and anti-icing ability. Due to the low price of this material, the developed composite coating has great potential in various industrial applications.