Surface properties of polydimethylsiloxane-based inorganic/organic hybrid films deposited on polyimide sheets by the sol-gel method

Polydimethylsiloxane (PDMS)-based inorganic/organic hybrids films were prepared on polyimide sheets by the sol-gel method using silanol-terminated PDMS and titanium tetraisopropoxide as starting materials. The effect of heat-treatment temperature on the surface property of the hybrid films was examined in terms of contact angle of water and Tapping-Mode Atomic Force Microscopy (AFM). AFM phase images showed the presence of domains, 200-500 nm in size, on the surface of these films after heat-treatment below 300degreesC. These regions were more hydrophilic than the rest of the area. The domains disappeared at 300degreesC and the surface became homogeneous surface of the peak to valley value, about 10 nm. It is also uniformly hydrophobic and a maximum contact angle (about 115degreesC) was obtained.