Zwitterionic fluorinated amphiphilic block copolymers prepared by RAFT polymerization for hydrophilic modification of PVDF membranes

Amphiphilic block copolymers exhibit significant application potential in multiple fields due to their unique hydrophilic-hydrophobic architecture. In this study, block copolymers of poly (methacryloyloxyethyl phosphorylcholine) (PMPC) and hexafluorobutyl methacrylate (PHFBMA), denoted as PMPC- b -PHFBMA with different compositions were successfully synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. The structures of the as-prepared copolymers were characterized by proton nuclear magnetic resonance ( 1 H NMR) and gel permeation chromatography (GPC). The results confirmed the successful synthesis of the copolymers and precise control over their chain segment lengths. Subsequently, PMPC- b -PHFBMA blended modified polyvinylidene fluoride (PVDF) ultrafiltration membranes were prepared by the nonsolvent-induced phase separation method, and the surface wettability and pure water flux of the membranes were systematically studied. The results showed that the water contact angle of the modified membranes was effectively reduced, and the pure water flux could be significantly increased to 1799.8 L/(m 2 ·h). This study demonstrates that the rationally designed amphiphilic block copolymer effectively enhances membrane hydrophilicity and filtration performance via surface segregation, underscoring its promising potential for high-performance separation membrane applications.