Synthesis and properties control of fluorinated organic-inorganic hybrid films

Fluorinated organic-inorganic hybrid films were prepared by free-radical random copolymerization and sol-gel process through dodecafluoroheptyl methacrylate (DFMA), vinyltriethoxysilane (VTES), and tetramethoxysilane (TMOS). It was found that the prepared fluorinated organic-inorganic hybrid film was very hydrophobic and exhibits excellent water repellency. Hydrophobic fluorocarbon side chains were preferentially enriched to the outermost layer at the interface of coating film-air, and three layers probably exist in the coating films. The fluorinated hybrid films possessed fluorocarbon side chains orient toward the air originating from DFMA as the top layer, hydrocarbon backbone chain originating from vinyl polymerization as the middle layer, and silica network originating from the hydrolysis and condensation of siloxane as the bottom layer. It demonstrated that most of TMOS added might be arranged to the bottom layer of the fluorinated hybrid films, and had a slight impact on the enrichment of fluorocarbon side chains of the outermost layer. However, the useful properties of the fluorinated organic-inorganic hybrid films such as thickness and corrosion resistant can be significantly improved by the increase of TMOS content. (C) 2011 Elsevier B.V. All rights reserved.