Poly(vinylidene fluoride)/polyethersulfone blend membranes: Effects of solvent sort, polyethersulfone and polyvinylpyrrolidone concentration on their properties and morphology

The effects of some membrane preparation conditions on the characteristics and performance of poly(vinylidene fluoride)/polyethersulfone membranes were studied. Poly(vinylidene fluoride) (PVDF) and polyethersulfone (PES) were employed as base polymers. Four different including dimethyl sulphoxide (DMSO), dimethyl formamide (DMF), 1-methyl-2-pyrrolidone (NMP) and dimethyl acetamide (DMAc) used as the solvents. Polyvinylpyrrolidone (PVP) was used as pore-forming additive. The preparation variables in this work were sort of content proportion of PVDF/PES, and concentration of PVP The flat-sheet membranes prepared by phase inversion were characterized using scanning electron microscopy (SEM). Membrane performance was evaluated by shrinkage ratio, pure water flux and retention to bovine albumin (BSA). The shrinkage ratio of PVDF/PES blend membrane was much reduced when DMAc was used as a solvent. The pure water of blend membranes reaches the maximum and the retention to BSA reaches the minimum when the casting solution contains 1.5 wt% PES 5 wt% PVP (c) 2006 Elsevier B.V. All rights reserved.