Abstract: The graft copolymerization of propyl methacrylate onto sweet patato starch was carried out using patassium permangate-acid as initiator.The effect of various conditions on the graft polymerization was studied.The results show that when the concentration of the monomer is 1.0 mol/L,the concentration of the initiator is 1.5 mmol/L,the reaction temperature is 40～50 ℃,the reaction time is 1.5 h,high efficient grafting(EG%) can be achieved.

Key words: graft copolymerization, propyl methacrylate, sweet patato starch, patassium permangate