New insights in poly(vinylidene fluoride) (PVDF) membrane hemocompatibility: Synergistic effect of PVDF-g-(acryloyl morpholine) and PVDF-g-(poly(acrylic acid)-argatroban) copolymers

Hydrophilic and hemocompatible surface design is vital for poly(vinylidene fluoride) (PVDF) membranes in biological application especially for hemodialysis. In this work, the influence and synergistic effect of PVDF-g-(acryloyl morpholine) (PVDF-g-ACMO) and PVDF-g-(poly(acrylic acid)-argatroban) (PVDF-g-(PAA-AG)) copolymers blending modification on structure and properties of PVDF membrane were investigated. The membranes were prepared through immersion phase transition method. The copolymer structure was characterized by FT-IR and 1H NMR. Modified membrane surfaces obtained were characterized by XPS. The blending modified PVDF hollow fiber membranes were confirmed to have excellent hydrophilicity, good hemocompatibility properties (protein adsorption, platelets/ red blood cells adhesion, plasma coagulation), good permeability and anti-protein fouling performance. The hydrophilic and anti-hemolytic properties were significantly improved with the weight percentage of PVDF-g-ACMO copolymer, and PVDF-g-(PAA-AG) copolymer endow the anti-coagulation of modified membranes. And when the blend ratio was up to 1:3, the blend membranes show the longest clotting time (APTT 114.15 s and PT 25.65 s). This work provides a new modification method to improve the hemocompatibility for PVDF membranes in potential biological applications.