Improved antifouling properties and blood compatibility of 3-methacryloxypropyl trimethoxysilane – based zwitterionic copolymer modified composite membranes via in situ post-crosslinking copolymerization

Abstract

In the present study, a new method to prepare stable antifouling and blood compatible membranes is developed, i.e., in situ post-crosslinking copolymerization. Firstly, 3-methacryloxypropyl trimethoxysilane (MTSi)-based zwitterionic copolymer was synthesized by in situ copolymerization in polyethersulfone (PES) solution and fabricated into membranes by a liquid–liquid phase separation technique. Then the membranes were treated by basic solutions to promote the crosslinking of the copolymer via the hydrolysis of the methoxy groups. The surface free energy of the poly(3-methacryloxypropyl trimethoxysilane) (PMTSi) modified membranes reduced from 55.29 to 43.91 nJ cm⁻². For the poly(3-methacryloxypropyl trimethoxysilane-co-sulfobetaine methacrylate) (P(MTSi-co-SBMA)) modified membranes, the hydrolyzed PMTSi segments were used as the crosslinker to make the membrane stable. Both the PMTSi and P(MTSi-co-SBMA) modified membranes showed improved antifouling property and blood compatibility (lowered protein adsorption amount, suppressed platelet adhesion and prolonged clotting time) compared with the pristine PES membrane. Thus the modified membranes provided wide choice for specific biomedical applications.