光照对含氟表面活性剂表面性质的影响

Effect of Light Irradiation on the Surface Properties of the Surfactant Having Fluorine

以对三氟甲基苯胺为起始原料,制备了一种部分氟化的表面活性剂CF-S,测定其紫外吸收光谱,研究其光异构化。测定CF-S溶液的表面张力,计算相应的物化参数,并与不含氟的表面活性剂CH-S的性能进行比较,结果发现,CF-S的表面活性明显强于CH-S的表面活性。在紫外光激发后,CF-S的cmc和γ_(cmc)增大,Г_(max)减小,A_(min)变大。CF-S对石英的润湿性能测试显示,含氟的表面活性剂能提高石英表面的疏水性。紫外光的照射使CF-S在石英表面的接触角降低,CF-S润湿性能增强。测定了石英在CF-S溶液中的动电位,加入CF-S后,石英表面的动电位增加。在紫外光照射后,石英的动电位降低,部分CF-S从石英表面脱附。

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.