On-uma Nimittrakoolchai and Sitthisuntorn Supothina

pp. 157 - 162

Abstract

Transparent, hydrophobic hybrid films were deposited on glass substrate from solution containing hydroxyl-terminated
polydimethylsiloxane (PDMS) and TiO₂
 sol by using a dip coating method. The effects of the film heat-treatment temperature
and PDMS/TiO₂
 component on surface properties of the hybrid films were investigated by water drop contact angle measurement, and by atomic force microscopy (AFM) and scanning electron microscope (SEM) analyses. Surface morphology of the
hybrid film changed from smooth surface containing tiny spikes to rougher surface containing large protrusions during heattreatment temperatures of 60 - 300°C and became smooth surface containing very fine spikes at 500°C, corresponding to a
change hydrophobicity behavior from contact angle measurement. The suitable condition for preparation of hydrophobic
coating from this current recipe was at the PDMS/TiO₂
 volume ratio of 1.00 - 2.33 and heat-treatment temperature of 60°C. All
the films were transparent regardless of post heat-treatment temperature. However, the films containing higher content of
PDMS were slightly more transparent.