摘要
Layer-by-layer assembly is a versatile technique for fabricating nanofiltration membranes,where multiple layers of polyelectrolytes are usually required to achieve reasonable separation performance.In this work,an ionic strength directed self-assembly procedure is described for the preparation of nanofiltration membranes consisting of only a single bilayer of poly(diallyldimethylammoniumchloride)and poly(sodium-4-styrenesulfoate).The influence of background ionic strength as well as membrane substrate properties on the formation of singlebilayer membranes are systematically evaluated.Such a simplified polyelectrolyte deposition procedure results in membranes having outstanding separation performance with permeating flux of 14.21.5 L∙m^(–2)∙h^(-1)∙bar^(–1) and Na2SO4 rejection of 97.1%0.8%under a low applied pressure of 1 bar.These results surpass the ones for conventional multilayered polyelectrolyte membranes.This work encompasses an investigation of ionic strength induced coiling of the polyelectrolyte chains and emphasizes the interplay between-polyelectrolyte chain configuration and substrate pore profile.It thus introduces a new concept on the control of membrane fabrication process toward high performance nanofiltration.
基金
supported by the National Key Research and Development Project(Grant Nos.2019YFC1711300 and 2019YFA0705800)
the National Natural Science Funds for Distinguished Young Scholar(Grant No.51625306)
the National Natural Science Foundation of China(Grant Nos.21988102 and 51873230)
the Social Development Program of Jiangsu Province(Grant No.BE2019678).
作者简介
Feng Zhang,E-mails:fzhang2018@suda.edu.cn;Jian Jin,jjin@suda.edu.cn。
