A novel dissolution and resolidification method for preparing robust superhydrophobic polystyrene/silica composite

The poor robustness under large pressure has become the bottleneck for the practical applications of the superhydrophobic surfaces. Here, we present a simple and inexpensive method for forming a superhydrophobic surface using polystyrene and an acetone based suspension of perfluorosilane-coated silica nanoparticles. The acetone is a suitable solvent to dissolve the PS which tends to form microscale roughness. Simultaneously, the nanoparticles are forced to get embedded into the PS surface during the resolidification process after evaporating the acetone. The combination of partially-embedded nanoparticles and hierarchical structure result in the robustness of as-prepared surface, which could withstand tape-peeling test (24.50 kPa) for at least 80 times and sandpaper abrasion (7.84 kPa) for 6.75 m without losing superhydrophobicity. Moreover, the as-prepared superhydrophobic surface maintains excellent self-cleaning properties in either air or oil environment.