Super-hydrophobicity of silica nanoparticles modified with vinyl groups

Super-hydrophobic films with vinyl-modified silica nanoparticles (V-SiOx-NPs) were successfully prepared. The rough surface, which was composed of microstructures of disordered V-SiOx-NPs and nanostructures on the surface of V-SiOx-NPs, rather than the chemical composition devoted to the super-hydrophobicity of film. The relationship between contact angle and diameter of V-SiOx-NPs was then investigated. The sessile contact angles (CA) of films with 150-1600 nm V-SiOx-NPs were around 166° regardless the diameter, while the film with 85 nm V-SiOx-NPs had the lowest CA of about 158°. The packing manner of V-SiOx-NPs determined the air fraction on the surface and then the CA.