The preparation of antifouling ultrafiltration membrane by surface grafting zwitterionic polymer onto poly(arylene ether sulfone) containing hydroxyl groups membrane

This work describes the polymerization of a zwitterionic polymer, poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] onto the poly(arylene ether sulfone) containing hydroxyl groups (PES-OH) membrane via redox graft polymerization using ceric (IV) ammonium nitrate (CAN) as initiator. Due to the presence of the activated hydroxyl groups which were used for the immobilization of MPC monomer, the grafting process is facile and effective which avoid the complex and unfavorable pretreatment process and/or hydroxylated treatment. Attenuated total reflectance Fourier transform infrared spectrometer (FTIR-ATR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to characterize the chemical compositions and surface morphologies of the unmodified (PES-OH) and modified membrane, respectively. Static water contact angle measurement indicated that the introduction of poly(MPC) promoted remarkably the surface hydrophilicity of the PES-OH membrane. The cycle ultrafiltration experiments for protein solution revealed that nonspecific protein adsorption, especially irreversible protein adsorption, for the zwitterionic membrane was significantly reduced, suggesting superior antifouling performance. This work not only introduces a modification approach to obtain a PES-OH membrane grafting hydrophilic poly(MPC) chains, but also gives the zwitterionic membrane a long time life and excellent ultrafiltration performance.

► Modification of the PES-OH membrane via redox graft polymerization.
► Poly(MPC) is immobilized by hydroxyl groups on the PES-OH membrane surface.
► The grafting process is facile and effective due to the presence of hydroxyl group.
► The zwitterionic membrane exhibits excellent protein antifouling property.