Abstract: A partially fluorinated surfactant, CF-S, was prepared using p-trifluoromethyl aniline as the starting material. Its UV-Vis spectrum was measured. The photoisomerization of CF-S was studied. The surface tension of the CF-S solution was measured. The corresponding physicochemical parameters were calculated. The properties of CF-S were compared with those of CH-S, a surfactant without fluorine. It was found that the surface activity of CF-S was significantly stronger than that of CH-S. After UV light irradiation, CF-S showed higher cmc and γ_cmc, lower Г_max and greater A_min. The wettability of CF-S to quartz was measured.The fluorinated surfactant can improve the hydrophobicity of the quartz surface. The contact angle of CF-S on the quartz surface was decreased by UV light irradiation. So the wettability of CF-S was increased. The Zeta potential of the quartz particles was measured in the CF-S solution. After adding CF-S into the solution, the Zeta potential of the quartz particles was increased. After UV irradiation, the Zeta potential of quartz was decreased. Some adsorbed surfactants were desorbed from the quartz surface.

Key words: fluorinated surfactant, light irradiation, surface properties, wettability, adsorption