Preparation of modified polyethersulfone membranes using variation in coagulation bath temperature and addition of hydrophilic surfactant

In this study, novel asymmetric polyethersulfone membranes were prepared from PES/PEG/Tween-20/NMP system via immersion precipitation. Pure water was used as gelation media. Simultaneous effects of variation in coagulation bath temperature (CBT) and addition of Tween-20 on morphology, wettabiliy, pure water permeation flux (PWF) and bovine serum albumin (BSA) rejection of the prepared membranes were studied by scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle measuring instrument and experimental set up. The obtained results indicate that the small addition of surfactants in the casting solution along with using the lowest level of CBT increases hydrophilicity of the PES membranes. Also it was found out that addition of Tween-20 in the casting solution along with increasing the CBT incites the formation of the bigger pores on the top surface and results in the formation of membranes with higher porosity in the sublayer.