纳米二氧化钛的表面改性研究

Study on surface modification of nano-sized titania

采用不同的表面活性剂三乙醇胺、十二烷基硫酸钠(SDS)、聚乙烯吡咯烷酮(PVP)对纳米二氧化钛进行表面改性处理。对不同表面活性剂处理的纳米二氧化钛采用沉降法来表征纳米粉体在水中的分散性,目的是日后用来制备更均匀的复合薄膜。研究结果表明:三乙醇胺与其他两种表面活性剂混合使用较单种表面活性剂处理后的纳米二氧化钛其分散效果会更好。分散纳米二氧化钛效果最佳的表面活性剂为三乙醇胺与十二烷基硫酸钠的混合物(质量比为2∶1),表面活性剂总用量为30%(质量分数),采用搅拌和超声时间都为15 min,纳米二氧化钛的初始沉降时间为2.5 h,完全沉降时间大于120 h。

Surface of nano-sized titania （ TiO2） was modified with different surfactants, such as triethanolamine, sodium dodecyl sulfate （ SDS ）, and polyvinyl pyrrolidone （PVP）. The dispersion of nano-sized TiO2 treated by different surfactants in water were characterized and analyzed by sedimentation method, so that it can be used to prepare more uniform composite membrane in future. Results showed that, nano-sized TiO2 was treated with three surfactants had better dispersion than that treated by single surfactant. Optimum dispersion effect could be obtained when the mix ratio of triethanolamine and SDS was 2：1 （mass ratio） ,total dosage of surfactants was 30% （mass fraction） ,stirring and ultrasonic time were both 15 min,initial settling time of nano-sized TiO2 was 2.5 h,and the completely settling time was above 120 h.