Polyethylene glycol cross-linked sulfonated polyethersulfone based filtration membranes with improved antifouling tendency

Highly hydrophilic and fouling resistant porous membranes were prepared by covalent cross-linking of sulfonated polyethersulfone with amino terminated polyethylene glycol. Polyether sulfone (PES) was sulfonated and cross-linked with poly(ethylene glycol) bis-(3-aminopropyl) terminated via sulfonamide linkage using 1,1′-carbonyldiimidazole (CDI). The characteristics, the stability, and the separation performance of the prepared cross-linked membranes were evaluated in detail. The membranes were characterized with respect to membrane chemistry (by ATR-FTIR spectroscopy), hydrophilicity and surface energy (by dynamic contact angle), surface morphology (by scanning electron microscopy), pure water permeability, and rejection of bovine serum albumin (BSA) protein. The antifouling properties of the prepared membranes were assessed by protein adsorption and bacterial cell adhesion study. The cross-linked membranes exhibited superior water permeation, rejection, and antifouling performance to the neat membrane. The protein adsorption on membrane surface was about 10-fold less than that of the PES membrane. The results reveal that, hydrophilicity was increased due to PEG, leading to the 3-fold increase in water flux and more than 90% protein rejection efficiency.