Various monomers were grafted onto polypropylene (PP) fiber via thermal cleavage of BPO. The monomers included acrylic acid and 3-(sulfopropyidimethylamino)ethyl-2-methylacrylate. Grafting percentage exceeded 100% in all cases. The grafted PP fiber was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and thermal analysis. (C) 2004 Published by Elsevier Ltd.