Improved biocompatibility and antifouling property of polypropylene non-woven fabric membrane by surface grafting zwitterionic polymer

This work described the graft polymerization of a zwitterionic polymer, [3-(methacryloylamino)propyl]-dimethyl(3-sulfopropyl) ammonium hydroxide (MPDSAH), onto polypropylene non-woven fabric (NWF) membrane via O2 plasma pretreatment and UV-irradiated technique. The surfaces of the modified NWF membranes were principally characterized using attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), and static water contact-angle measurement. The wettability was measured by water contact angle and equilibrium water adsorption. It was found that the water contact angles for the membranes decreased from 123° to 17° with increasing grafting density of poly(MPDSAH) from 0 to 349.2 μg/cm2, while the equilibrium water adsorption reached a maximum at the grafting density of 120.5 μg/cm2. The decreases of protein adsorption and platelet adhesion on the modified membrane revealed the enhancement protein resistance and excellent resistance to platelet adhesion due to the incorporation of zwitterionic poly(MPDSAH). Besides, microfiltration experiments were carried out to test the antifouling properties. Water flux recovery ratio was achieved as high as 90% for the modified membrane with respect to only about 30% for the neat NWF membrane.