聚醚砜超滤膜的结构与性能

Structure and Property of Polyethersulfone Ultrafiltration Membrane

采用相转化法制备聚醚砜超滤膜 ,测定了膜的水通量及对维生素B12 截留率 ,并通过SEM观察了膜皮层与断面形态。研究了膜亚层中大空腔的形成 ,探讨了铸膜液中聚醚砜质量分数对膜性能的影响以及磷酸添加剂对膜结构与性能的影响。皮层的形成对亚层结构有很大影响 ,铸膜液适宜的PES质量分数为 1 2 %～1 8% ,在铸膜液中加入少量的磷酸可以调节膜皮层形态。

Polyethersulfone(PES) ultrafitration membranes were prepared by a phase-inversion method. The water flux and the rejection of the membranes for vitamin B_ 12 were measured and their top layer and cross section morphology were observed by SEM. The formation of macrovoids in the sublayer of the membranes, effects of polyethersulfone mass fraction in the casting solution, as well as the presence of phosphoric acid on the structure of sublayer and property of the final membranes had been investigated. It was found that formation of top layer had a significant effect on the structure of the sublayer of membrance. The appropriate PES mass fraction appeared in between 12% and 18%. Morphology of top layer, structure of sublayer and property of the membranes could be controlled by addition of a small amount of phosphoric acid to the casting solution.