Preparation and properties of titanium oxide/polyurethane superhydrophobic coating

A nano-titanium oxide (TiO2)/polyurethane (PU) micro-nano composite superhyd rophobic coating was prepared by a simple spraying process. In this process, TiO2 and organosilicon-modified PU were used as raw materials, and ethyl acetate was used as dispersing agent. The water contact angle (CA) and sliding angel(SA) of the coating surface are 156° and 3°, respectively. After UV irradiation, the coating surface becomes a superhydrophilic surface, the CA is 3°. The coating surface morphology was characterized via scanning electron microscopy. The influence of the mass ratio of TiO2 and PU, and irradiation time on the coating surface wettability reversal was studied. The results show that the coating surface has the similar micro-nanostructure as the lotus leaf surface. When the mass ratio of TiO2 and PU is between 3:5 and 4:5, and the irradiation time is longer than 3 h, the coating surface wettability reverses obviously. ©, 2015, Chengdu University of Science and Technology. All right reserved.