Abstract
Silica films were prepared from a mixture of polymerized tetraethoxysilane (Si(OC2H5)4) and modified polydimethylsiloxane (PDMS) by the sol-gel spin-coating method. The modified PDMS used in this study was monosilanol-both-terminated PDMS (HO{Si(CH3)2O}nSi(CH3)2OH) and trisilanol-both-terminated PDMS synthesized from monosilanol-both-terminated PDMS and 3-isocyanatepropyltrimethoxysilane (OCN-C3H6Si(OCH3)3). The surface morphology observed in the resultant films was flatness for monosilanol-both-terminated PDMS or uneven for trisilanol-both-terminated PDMS, respectively. The periodic scale of unevenness changed with polymerization degree of PDMS and the height of unevenness was controlled by changing humidity at coating operation. Furthermore, the composition ratio of PDMS to silica in a coating solution influenced the surface morphology. We think that the uneven morphology of hybrid films was formed due to phase separation during drying wet films on a glass substrate.
