纳米TiO2对不同材料超滤膜结构与性能的影响

选用聚醚酮(PEK)、聚醚砜(PES)、酚酞聚醚砜(PES-C)3种不同的高分子材料,用浸没沉淀相转化法制备了一系列不同纳米TiO2含量的纳米TiO2复合膜,并通过扫描电子显微镜(SEM),X射线能谱仪(EDS),水接触角测试及超滤实验考察了纳米TiO2对膜的结构及性能的影响.结果表明,纳米TiO2与高分子超滤膜的复合显著改善了膜的亲水性.在截留率较高且基本保持不变的情况下,3种超滤膜的纯水通量和BSA溶液通量都得到了不同程度的提高.而由EDS分析可知,经过一定的时间,膜表面的TiO2会部分脱落,TiO2粒子与膜表面结合的稳定性问题不容忽视.在选用的3种材料中,TiO2粒子与PES-C膜表面结合较为牢固,且复合后BSA溶液通量的增幅最大,通量衰减较小,具有更好的膜结构和性能.

The influence of TiO2 nanoparticle on structure and performances of different ultrafiltration membranes

In this study,three different TiO2/polymer nanocomposite membranes were prepared via the immersion precipitation phase inversion process,including TiO2/PEK,TiO2/PES,TiO2/PES-C UF membranes.The influences of TiO2 nanoparticles on structure and performances of ultrafiltration membrane were investigated by scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS),contact angle goniometer,UF experiments.The results show that the hydrophilicity of the membranes were improved.Both the pure water fluxes and BSA aqueous fluxex were increased by the addition of nano-sized TiO2 particle.However,EDS spectra showed that the nanoparticles on the surface of nanocomposite membranes were partially removed after a period of time.The stability of the TiO2 nanoparticle is a critical problem that can't be neglected.Among the three kinds of materials,the nanoparticles were attached more firmly on the TiO2/PES-C membrane surfaces.Furthermore,not only the BSA aqueous fluxes of TiO2/PES-C were evidently increased,but also the BSA aqueous flux reduction was smaller.The TiO2/PES-C UF membranes were superior on structure and performances.