Novel antifouling polysulfone matrix membrane modified with zwitterionic polymer

Abstract Functional matrix membranes formed by blending hydrophilic polymers with polysulfone (PSF) can provide functional surfaces with ameliorative hydrophilicity and possess excellent antifouling resistance over a wide range of applications. Zwitterionic polymers have better antifouling properties, but their homopolymers should not be used directly because of their poor mechanical properties and strong water absorption. To solve these problems, a living radical polymerization process was used to prepare P(4VPx-r-SBMAy) copolymers comprising of zwitterion side chains and hydrophobic 4-vinylpyridine (4VP). The modified PSF membranes were then constructed by adding different ratios of P(4VPx-r-SBMAy) via phase inversion/immersion precipitation technique. The presence of 4VP and zwitterion chains of copolymer was verified by 1H nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) analyses, and the successful surface functionalization was further confirmed with atomic force microscopy (AFM), scanning electron microscopy (SEM) and water contact angle measurement. Protein adsorption, bacterium adhesion and cell attachment assays showed that the functional PSF membrane surfaces exhibited superior hydrophilicity and antifouling performance.