文献类型：期刊文献

英文题名：Microporous polyethersulfone membranes prepared under the combined precipitation conditions with non-solvent additives

作者：Li, Jing-Feng[1];Xu, Zhen-Liang[1];Yang, Hu[1]

机构：[1]E China Univ Sci & Technol, Membrane Sci & Engn R&D Lab, Chem Engn Res Ctr, Shanghai 200237, Peoples R China

年份：2008

卷号：19

期号：4

起止页码：251

外文期刊名：POLYMERS FOR ADVANCED TECHNOLOGIES

收录：;EI(收录号：20081711210029);WOS:【SCI-EXPANDED(收录号:WOS:000254945800001)】；

语种：英文

外文关键词：polyethersulfone (PES); microporous membrane; immersion precipitation; light transmittance; non-solvent additive (NSA)

摘要：Using diethylene glycol (DegOH) as non-solvent additive (NSA) and N, N-dimethylacetamide (DMAc) as solvent (S), polyethersulfone (PES) flat sheet membranes were prepared via immersion precipitation combined with the vapor induced phase separation (VIPS) process. Light transmittance was used to follow the precipitation rate during the immersion process as well as during the VIPS stage. As the addition of the NSA, the viscosity of casting solutions increased, which led to a slow precipitation rate. Though the precipitation rate decreased, the instantaneous demixing type was maintained. High flux membranes were obtained only at a high mass ratio of NSA/S; producing membranes had cellular pores on the top surface and sponge-like structure on cross section. The VIPS process prior to immersion precipitation was important for the formation of cellular pore on the surface. With the increase in exposure time, the liquid-liquid phase separation took place on the surface of casting solution; nucleation and growth induced the formation of cellular pore on the top surface. Coagulation bath temperature also had large effect on the precipitation rate; high temperature on coagulation bath mainly accelerated the transfer of solvent and non-solvent. Higher flux membrane with a porous skin layer could be obtained at a high coagulation bath temperature, but at the same time the mechanism properties were weakened. Copyright (C) 2007 John Wiley & Sons, Ltd.