Structure and gas separation properties of composite films based on polyaniline

Composite films based on the polyvinyltrimethylsilane (PVTMS) with polyaniline (PANI) coating were obtained by borderline polymerization of aniline. The obtained coating was shown to differ from the polymer forming in the reaction mixture bulk both in chemical structure and morphology. Ratio and concentration of the reagents, mixing rate, reaction time, and condition of support surface were among the investigated factors affecting the growth and quality of PANI coating. The gas separation characteristics of composite membranes, as affected by the process conditions and the type of PANI, were investigated. It is shown that the proposed method provides a means for obtaining composite membranes that combine high selectivity, especially in O-2/N-2, He/CH4, and CO2/CH4 separation, with permeability higher than that of known composite materials. (C) 2003 Wiley Periodicals, Inc.