Zwitterion-Functionalized Graphene Oxide Incorporated Polyamide Membranes with Improved Antifouling Properties

In this study, zwitterionic polymer poly(sulfobetaine methacrylate) (PSBMA) functionalized graphene oxide (GO) nanocomposites (GO-PSBMA) were synthesized and incorporated into the active layer of a polyamide membrane to improve its water perm-selectivity and fouling-resistant properties. GO-PSBMA nanocomposite contained covalently tethered PSBMA brushes on GO sheets, which were grown by activators regenerated by the electron transfer–atom transfer radical polymerization technique via the “graft-from” strategy. The grafting of zwitterionic PSBMA partially neutralized the surface charge of GO and increased its dispersibility in organic solvent. The incorporation of the GO-PSBMA-1h nanocomposite in the active layer of the polyamide membrane significantly improved surface hydrophilicity of the membrane and reduced its charge density. A near twofold increase in water permeation flux, with the nonsignificant change in MgSO4 and NaCl rejection, was achieved after the incorporation of 0.3 wt % of GO-PSBMA-1h in t...