Integrating radical polymerization and non-solvent induced phase inversion strategy for functionalized ultrafiltration membrane fabrication

The facile fabrication of high-performance membranes with attractive water permeability, retention ability, and fouling resistance holds a significant interest within the realm of membrane technology advancement. In this study, we developed an integrated radical polymerization and non-solvent induced phase separation strategy for functionalized ultrafiltration membrane fabrication. This innovative approach enabled the compositive of membrane preparation and functionalization by introducing a radical initiator into the casting solution and incorporating functional monomers into the coagulation bath. We demonstrated the effectiveness of this integrated membrane fabrication method by using zwitterionic sulfobetaine methacrylate (SBMA) as a classic test case. By optimizing radical polymerization time, the SBMA/PVDF membrane achieved simultaneous enhancements in water flux (187.6 L m-1 h-1), retention ability (99.0 % rejection for BSA protein), and antifouling property (9.8 % improvement) compared with the pristine PVDF membrane. Additionally, the microstructure, hydrophilicity, and zeta potential of SBMA/PVDF membranes were deliberately controlled by regulating the radical polymerization time. Furthermore, we demonstrated the universal applicability of the integrated membrane fabrication method by replacing SBMA with antimicrobial agent monomers in the coagulation bath. Our research contributes to the field of functionalized ultrafiltration membrane fabrication by developing the integration strategy of radical polymerization and non-solvent induced phase separation.