Fluorocarbon-organosilicon copolymer synthesis by hot filament chemical vapor deposition

Hot-filament chemical vapor deposition has been used to deposit copolymer thin films consisting of fluorocarbon and organosilicon groups from hexafluoropropylene oxide (HFPO) and hexamethylcyclotrisiloxane (D-3). This method offers an easy route to the production of such copolymers as the process does not require a solvent and can be performed in a single step. The presence of covalent bonds between the fluorocarbon and organosilicon moieties in the thin films has been confirmed by infrared spectroscopy; X-ray photoelectron spectroscopy (XPS); and solid-state F-19, C-13, and Si-29 nuclear magnetic resonance (NMR) spectroscopy. The film structure consists of chains with linear and cyclic siloxane groups and CF2 groups as repeat units. Cross-linking and termination occur mainly via the siloxane units.