Engineering bio-inert and thermostable poly(vinylidene difluoride) membranes by grafting thermal-tolerant copolymers via ring-opening reaction

• Thermostable and bio-inert PVDF membranes developed via SMA grafting. • Poly(acrylamide-r-N-vinylpyrrolidone) grafted to enhance antifouling properties. • Membranes maintain bio-inert and antifouling performance post-sterilization. • SMA simplifies the grafting process and improves hydrophilicity of PVDF membranes. • Up to 97 % bacterial adhesion reduction achieved with grafted PVDF membranes. This study explores the development of a thermostable and bio-inert PVDF membrane by grafting poly(acrylamide- r -N-vinylpyrrolidone) (P(AA- r -NVP)) onto a styrene- co -maleic anhydride (SMA)-functionalized PVDF substrate. The fabrication process involved blending SMA into the PVDF matrix followed by vapor-induced phase separation process to form the porous membrane. P(AA- r -NVP) was then grafted onto the membrane through the ring-opening of maleic anhydride groups. Characterization through ATR-FTIR and XPS confirmed successful surface modification. Antifouling performance of the membranes were assessed through bacterial adhesion tests before and after steam sterilization. Before sterilization, SMA3_A3V7 effectively resisted up to 97 % of E. coli adhesion. After steam sterilization, SMA3_A3V7 demonstrated excellent thermal stability, with a minimal 1.25 % increase in bacterial adhesion, compared to a 250 % increase in the unmodified PVDF membrane. These findings feature the effectiveness of utilizing SMA in simplifying the grafting process and the contribution of the thermostable and bio-inert polymer in imparting high-temperature resistance and antifouling resistance to the membrane, enabling versatile applications.