Modification of polysulfone membranes using triblock copolymer of polyethylene glycol and polypropylene glycol

Abstract

The phase state, viscosity and optical properties of polysulfone (PSF) solutions in N,N-dimethylacetamide (DMAc) with the addition of block copolymer Pluronic F127 and polyethylene glycol (PEG-4000, M n = 4000 g-mol -1 ) were studied. Additives are both pore-forming and hydrophilizing agents. It was found that 18-22 % PSF solutions in DMAc with the Pluronic F127 content t ≥5 wt. % feature a lower critical solution temperature (LCST). Mixed matrix PSF/Pluronic F127 and PSF/PEG membranes were obtained by the phase inversion technique and the comparative studies of their structure and performance were carried out. It was found that the average surface roughness parameters of PSF/Pluronic F127 membranes significantly exceed those of PSF/PEG membranes. The presence of the both additives in the casting solution leads to the effective hydrophilization of the membrane selective layer. It was shown that the increase in the membrane flux and the decrease in the polyvinylpyrrolidone (K-30, M n = 40000 g-mol -1 ) rejection coefficient are a result of adding both Pluronic F127 and PEG-4000 to the casting solution. It was shown that PSF/Pluronic F127 membranes are characterized by higher shrinkage resistance and a lower total flux decrease during ultrafiltration of bovine serum albumin solutions. It was found that the antifouling performance of PSF/Pluronic F127 membranes significantly exceeds that of PSF/PEG membranes.