Green synthesis of polyvinylidene fluoride ultrafiltration membrane with upgraded hydrophilicity

Abstract

The use of Cyrene™ as an alternative non-toxic solvent to produce a PVDF-based ultrafiltration membrane was investigated in this study. Polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) were used as organic additives to explore its ability to improve membrane hydrophilicity. The additives were introduced into the casting solution via phase inversion with a combined non-solvent induced phase separation (NIPS) and evaporation-induced phase separation (EIPS) technique. The prepared membranes were characterized to examine its morphology, mechanical properties, and filtration performance. The results show that the addition of PEG and PVP has proven able to improve the membrane hydrophilicity with the lowest contact angle of 76.81° achieved from the addition of PEG with concentration 3 wt%. However, the nascent membranes were not adequate enough, in terms of its mechanical properties, to undergo performance tests due to its very brittle nature. The overall results from this study demonstrate a great potential as a proposed method of utilizing Cyrene™ as a choice of green solvent to fabricate PVDF-based ultrafiltration membrane with the incorporation of PEG and PVP as organic additives.