Abstract: A twin-monomer-grafted polypropylene (PP)-based modifier was prepared by using N-vinyl pyrrolidone (NVP) and poly(ethylene glycol methacrylate) (PEGMA) as monomers through a melt grafting method. The resulting graft copolymer was characterized by elemental analysis, Fourier-transform infrared (FTIR) spectroscopy, protein adsorption experiment and contact angle test. FTIR analysis indicated that the two monomers were grafted onto PP successfully. The grafting rate of NVP on PP could be improved by the addition of a small amount of PEGMA, and the graft copolymer achieved a grafting rate of 21.36 wt % for NVP and 3.82 wt % for PEGMA. The graft copolymer exhibited good hydrophilicity, and its water contact angle decreases from 105 ° to 53 °. The graft copolymer also can restrain the adsorption of protein effectively, so the membrane made from this graft copolymer is expected to have a good anti-pollution capability.

Key words: polypropylene, N-vinyl pyrrolidone, poly (ethylene glycol methacrylate), grafting rate, water contact angle