Performance Improvement of Polysulfone Ultrafiltration Membrane Using Well-Dispersed Polyaniline–Poly(vinylpyrrolidone) Nanocomposite as the Additive

Well-dispersed polyaniline–poly(vinylpyrrolidone) (PANI–PVP) nanocomposite was synthesized through dispersion polymerization and then used as a novel additive to prepare a polysulfone (PSf)/PANI–PVP nanocomposite membrane via immersion precipitation process. During membrane formation, a portion of PVP acted as a pore-forming agent while another PANI–PVP nanocomposite, combined by hydrogen bonds between carbonyl groups of PVP and N-hydrogen groups of PANI, acted as a hydrophilic modification agent. The addition of PANI–PVP nanocomposite increased membrane surface pore size, porosity, and hydrophilicity. Pure water fluxes of PSf/PANI–PVP nanocomposite membranes were 1.8–3.5 times that of PSf membrane with a slight change of bovine serum albumin (BSA) rejection. The membrane antifouling property was examined by the cross-flow ultafiltration using BSA solution as the model system. The results of flux decline behavior and flux recovery ratio showed that PSf/PANI–PVP nanocomposite membranes had an excellent antifouling property. Compared with PSf/PVP membranes prepared using PVP as the additive, PSf/PANI–PVP nanocomposite membranes processed higher pure water flux and better hydrophilicity, antifouling property, and stability.