Abstract: PP-g-NHA and PP-g-NHA/St have been prepared via melt grafting by using a twin-screw extruder using dicumyl peroxide (DCP) as an initiator. FTIR confirmed the grafting of NHA and St onto polypropylene (PP) chains. The effect of the content of monomer, initiator, extrusion temperature, and screw speed on the grafting degree and the resulted contact angle of grafted PP were investigated. When the content of NHA was 3%, the obtained grafting degree and contact angle were 1.6 % and 83°, respectively. With increasing loading of DCP, the grafting degree increased and then decreased. The screw speed should be higher than 40 r/min.

Key words: polypropylene, melt grafting, hydrophilicity, hydroxymethyl acrylamide