Preparation of Enduringly Antifouling PVDF Membrane with Compatible Zwitterionic Copolymer via Thermally Induced Phase Separation

The compatible zwitterionic copolymers of poly(methyl methacrylate [3-(methacryloylamino) propyl] dimethyl(3-sulfopropyl) ammonium-hydroxide) p(MMA-MPDSAH) with different MPDSAH ratio are synthesized by free radical polymerization. A serial of copolymers are obtained successfully with narrow molecular weight dispersion. The MPDSAH branch ratio varies from 5% to 20%. It is initially applied to fabricate enduringly antifouling poly(vinylidene fluoride) (PVDF) membrane through a simple approach of blending by thermally induced phase separation (TIPS). The influence of zwitterionic copolymer on membrane morphology is studied by scanning electron microscopy. It was proven effective to improve the hydrophilic property of PVDF membrane as the water contact angles dramatically decreased from 80 degrees to 40 degrees, leading to a significant enhancement of antifouling ability. The absorbed bull serum albumin (BSA) content on modified membranes has cut almost 50%. The residual content of p(MMA-MPDSAH) in membrane is over 40% and able to reach 80% even at vigorous rinsing by controlling copolymer structure. It guarantees the modified membrane has vested enduringly antifouling ability. (C) 2014 Wiley Periodicals, Inc.