Dual-mode antifouling ability of PVDF membrane with a surface-anchored amphiphilic polymer

Abstract

Polydimethylsiloxane-graft-polyethylene glycol (PDMS-graft-PEG), an amphiphilic polymer with four hydrophilic arms, was prepared and used to improve the antifouling property of PVDF membranes by a dip-coating method. The interface properties of the modified PVDF membranes were investigated and it was found that the increased molecular weight of the PEG segment exhibited a negative effect on the anchoring ability of the PDMS-graft-PEG on the membrane surface. However, the antifouling properties of the modified membranes were significantly improved due to the dual-mode antifouling ability of fouling repulsion (PEG) and fouling release (PDMS). The adsorption mass of BSA on the modified membrane surface decreased to a low level, and an enhanced water flux recovery ratio after washing (FRR-W) of the modified membranes was obtained for two typical pollutants of bovine serum albumin and sodium alginate. It was demonstrated that surface anchoring is an effective way to improve the interface characteristics of membrane materials with functional polymers.