Porometry Studies of the Polysulfone Membranes on Addition of Poly(ethylene Glycol) in Gelation Bath During Preparation

Polysulfone membranes are prepared through phase separation technique, introduced by Loeb-Sourirajan. The viscous polymer solution (in dimethyl formamide) is first spread into the thin film, and then immersed in gelation medium (water). The influence of polymeric additive, (poly(ethylene glycol) (PEG)) in the formation of the pores during phase separation in gelation bath (i.e. from the polymer poor phase, which appears at the phase separation) is explored. The effects of different molecular weight (Mw) of PEG in the gelation bath regarding the differential filter flows of nitrogen as well as their concentration are reflected from the porometry studies. The pore distribution is shifted as the molecular weight of PEG used in the gelation bath. The bubble point and mean flow pore diameters vary with the concentration as well as their molecular weight of PEG.