Investigation of the synergistic effect of titania micro and nanoparticles on the hydrophobic properties of polyurethane composite coating

One of the ways to improve the performance of ceramic insulators in polluted climates is to use polymer coatings reinforced with ceramic particles. The purpose of this study is to compare the effect of adding Titania nanoparticles and Titania micro-nanoparticles on hydrophobic properties of PU. In this method, stearic acid, which is a cheap and environmentally friendly material, was used for surface modification of TiO2. FTIR analysis was conducted to ensure that Titania was modified. nanocomposite and micro-nanocomposite (hybrid) coatings on glass and free films of polyurethane-titania containing 1%wt and 3%wt  titania were prepared using a simple and inexpensive method based on magnetic stirring and ultrasonication. AFM analysis and surface topography FESEM images showed higher increase in surface roughness in hybrid composites compared to the nanocomposite samples. The contact angles of the hybrid composites were also higher than those of the nanocomposites with the same Titania content. The hybrid sample containing 0.5%wt nanoparticles and 0.5%wt microparticles had the maximum contact angle. The contact angle of this sample increased by 22◦.