Hydrophobic inorganic–organic thin films with a low coefficient of friction

Organic–inorganic composite thin films based on polymethacrylate (PMMA)/SiO2 hybrids with controlled thickness and hydrophobicity have been synthesized. The in situ derivatization of the precursor solution by perfluoroalkylsulfonyl alkyl triakoxy silane C8F17SO2NHC3H6Si (OCH3)3 (trade name FC-922; Wuhan Yangtse River Chemical Plant, China ) effectively increases the hydrophobicity of the film, and the contact angle for water is more than 100°. Coefficients of friction 0.07−0.09 can be obtained for the in situ derivatized hybrid dip-coating films. These films are meeting practical lubricant and protection processing requirements, including low processing temperature, high thermal stability, and reliable mechanical properties.