Enhancing the Antifouling Properties of Polysulfone Ultrafiltration Membranes by the Grafting of Poly(Ethylene Glycol) Derivatives Via Surface Amidation Reactions

ABSTRACTA carboxylic acid group was introduced on the polysulfone (PSF) membrane surface through a Friedel–Crafts reaction. Then, three kinds of poly(ethylene glycol) (PEG) derivatives were chosen to be immobilized on the PSF membrane surface via amide bonds. The membrane surface morphology, chemical composition, and hydrophilicity were investigated with scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and water contact angle. The results indicate that PEG derivative immobilization effectively improved the antifouling properties of the PSF membranes. We found that prolonging the Friedel–Crafts reaction time or choosing the proper PEG derivative [methoxy poly(ethylene glycol) 550] could increase the surface hydrophilicity effectively and thus render the modified membranes better antifouling properties. The long‐term ultrafiltration experiment demonstrated the improvement of recycling properties and the reliability of the surface modification process. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41870.