Performance and properties of modified poly (vinylidene fluoride) membranes using general purpose polystyrene (GPPS) by DIPS method

An attempt has been undertaken to improve hydrophilic characteristics of poly(vinylidene fluoride) (PVDF) membrane by blending with amorphous polymer, polystyrene (GPPS) using conventional method of diffusion induced phase separation (DIPS). Blends of PVDF and GPPS have been prepared in 100:00, 95:05, 90:10, 85:15 and 00:100 ratio combinations. The morphology of blend membranes was investigated using scanning electron microscope (SEM), crystallite size and crystallinity was investigated using X-ray Diffractometer (XRD), pure water flux (PWF) and contact angle etc were also used. Pure water flux of 5% and 10% GPPS blend membranes went up to 14.0 and 16.5 Lm−2 h−1as compared to10.9 Lm−2 h−1 for 100% PVDF membrane. Crystallinity and crystallite size of the PVDF–GPPS membranes reduced with increase in GPPS content in PVDF. However, according to our observation excess of 15% GPPS in blend membrane showed an incompatibility and heterogeneity in PVDF–GPPS membrane structure. The treatment of distillery effluent through 100% PVDF, 5% and 10% GPPS blend membranes was investigated and high molecular weight organics were separated.

Cross section image of 10% GPPS membrane prepare in SLS coagulation bath.Figure optionsDownload as PowerPoint slideResearch highlights
► PVDF and GPPS blend membrane.
► Reduction of degradation temperature with addition of GPPS.
► Membranes exhibit a macro-void structure when 10% of GPPS is added.
► 87% COD removed with 5% and 10% GPPS blend membranes.