Improving the hydrophilicity and antifouling performance of PVDF membranes via PEI amination and further poly (methyl vinyl ether-alt-maleic anhydride) modification

Polyvinylidene fluoride (PVDF) is an excellent material for porous membranes due to its outstanding chemical resistance, thermal stability, and film formability. However, the lower surface energy and the hydrophobicity of PVDF, result in poor wettability and organic fouling. In the present work, polyethyleneimine (PEI) was covalently bound on PVDF through the amination reaction in the casting solution. After converting the solution into membranes by phase inversion, the PEI-aminated PVDF membrane was further modified with poly (methyl vinyl ether-alt-maleic anhydride) (PEOSMA). The PEOSMA-modified membranes possess super hydrophilicity and antifouling performance. The protein adsorption capacity of the modified membrane was extremely low, only 5.65 μg/cm2. The pure water recovery rate (FRR) reached 97%, with BSA rejection over 97%. The presented protocol offers an effective in-situ covalent modification method for PDVF membranes with a high potential in large-scale applications.