The cationic photopolymerization of oxetane-based systems containing silicon monomers was investigated. For this purpose, three new silicon-containing oxetane monomers were synthesized through a simple and straightforward synthetic method. The silicon-containing monomers were added to a typical oxetane resin, 3,3'-[oxydi(methylene)]bis(3-ethyloxetane), in concentrations of 1-5 wt %. They exploited a certain surface tension effect without affecting the rate of polymerization. Enrichment only on the air side was achieved, which induced hydrophobicity in the photocured films, depending on the monomer structure and concentration. (C) 2004 Wiley Periodicals, Inc.