Preparation and properties of hydrophobic organic-inorganic silica hybrid films

Hydrophobic organic-inorganic silica hybrid films were prepared by means of a two-step acid-catalyzed method and sol-gel process using surfactant as template. Methyltriethoxysilane(MTES) and tetraethoxysilane(TEOS) were co-hydrolyzed in different molar ration and were used as precursors. Addition MTES in TEOS precursors produces a decrease of Si-OH and Si-O- surface content. The infrared spectra of the films thus obtained indicated that they become hydrophobic with the introduction of the methyl groups. Contact angle instrument was also used to supplement the result. Contact angle values for hydrophobic hybrid films are greater than120 degree. The refractive indices and thickness of hydrophobic hybrid films are about 1.22-1.24 and about 270-300nm The Optical transmittance spectra and mechanical intensity measurement results showed that the films have good optical and mechanical properties.