Protection group assisted non-solvent induced phase separation for PO3H2 functionalized PVDF ultrafiltration membranes with a heavy metal removal capability

Fluorine-containing polymer membranes, such as Poly(vinylidene fluoride) (PVDF), getting intensive attention in the waste treatment field. While these polymers have exceptional mechanical and chemical stability, their inherent hydrophobic nature significantly limits water permeability. In this study, we first propose a novel fabrication method to enhance the water permeance and heavy metal removal capability of PVDF membranes using protection chemistry. The protection group-assisted non-solvent induced phase separation (PG-NIPS) method, combined with a potentially ionizable copolymer additive, successfully incorporates an amphiphilic copolymer into the PVDF matrix, resulting in superior water permeance while maintaining its morphological structure. Moreover, the phosphoric acid functional group in PVDF membranes provides additional metal removal capacity and fouling resistance against organic pollutants. This innovative fabrication method demonstrates the possibility of protection chemistry in membrane fabrication, and PVDF-CP membranes are poised to play a crucial role in addressing future water pollution challenges.