Hydrophilic Modification and Application of Polyvinylidene Fluoride‐Based Blend Membrane

Leveraging the hydrophilivity of methacryloxyethyl ammonium chloride (DMC), a PVDF‐g‐DMC copolymer was synthesized via alkali treatment and then blended with PVDF. A blended membrane was prepared using the non‐solvent induced phase seperation (NIPS) method. This membrane exhibited a pure‐water flux of 355.33 L/(m 2 ·h), significantly exceeding that of a pure PVDF membrane (203.12 L/(m 2 ·h)). The surface zeta potential of the blended membrane was −27.5 mV, indicating a reduced negative charge compared to PVDF membrane (−33.2 mV). The blended membrane also demonstrated superior performance with a BSA rejection rate of 91.65% (vs. 68.22% for PVDF membrane), enhanced antifouling properties, and a flux recovery rate (FRR) of 72.39%. Furthermore, the blended membrane showed improved acid acid and alkali resistance, with significantly smaller flux declines after 4 weeks immersion. In methylene blue (MB) solution, the blended membrane achieved a rejection rate of 70.99% and an FRR of 82.86%, underscoring its strong potential for wastewater treatment, particularly for the removal of charged dyes.