Surface Hydrophilicity and Morphology Control of Anti-Biofouling Polysulfone Membranes via Vapor-Induced Phase Separation Processing

We report in this study the formation of low-biofouling polysulfone (PSf) membranes by vapor-induced phase separation. Membranes were prepared by blending an amphiphilic additive, Pluronic (R) F108, Pluronic (R) F127 or 3-(N,N-Dimethylmyristylammonio)propane-sulfonate (DMMSAPS) with PSf, before inducing phase separation of the solution. The additive affected both membrane morphology and surface chemical composition. F127 and DMMSAPS tended to increase the porosity of membranes, while the final structure of membranes prepared with F108 were close to that of virgin PSf membrane. The additive molecular weight as well as micelle formation is believed to be responsible for these different porous structures. Whatever the additive, hydrophilicity of membranes was enhanced. Protein adsorption tests performed with PEGylated PSf membranes revealed that both F108 and F127 led to a decreasing of biofouling, but better performances were obtained using F127 for which stronger interactions with membrane matrices were achieved.