Preparation of PVDF/PES Blend Membranes for Cold Sterilization of Water and Milk

Abstract This study investigates the effect of coagulation bath composition and the concentration of polyethersulfone (PES) and polyvinylpyrrolidone (PVP) on the casting solution and evaporation time on the performance and morphology of polyvinylidenefluoride/polyethersulfone blend membranes. The membranes were prepared via immersion precipitation using polyvinylidenefluoride (PVDF) as a base polymer, dimethylacetamide as a solvent, acetone as a volatile solvent, and PVP and PES as additives. The flat sheet membranes were characterized by scanning electron microscopy. Membrane performance was evaluated by estimating flux and rejection using water and milk as the feed, both containing Escherichia coli bacteria. By introducing 2‐propanol in the coagulation bath, the flux of the prepared membrane was diminished. The addition of PES in the casting solution improved the flux. Introducing PVP affects the hydrophilicity and viscosity of the casting solution. Depending on the concentration of PVP and PES, the overall effect may improve or diminish the membrane flux. © 2011 Wiley Periodicals, Inc. Adv Polym Techn 32: E141–E152, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/adv.20278