Preparation and Application of the Graft Copolymer of Cationic Starch and Acrylamide

The graft copolymer was synthesized with low DS cationic starch and acrylamide initiated by (NH_4)_2Ce(NO_3)_6 in this paper.The effects of acrylamide to cationic starch mass ratio,reaction temperature, reaction time and initiator concentration on graft ratio and graft efficiency were investigated.It was found that the conditions of graft copolymerization with the highest graft ratio and graft efficiency were as follows:the mass ratio of acrylamide to cationic starch was 2.5:1;the concentration of initiator was 2 mmol/L;the reaction temperature was 55℃and the reaction time was 3 h.When the graft copolymer was used as paper strength additive at a dosage of 1.0%,the paper tensile index,tear index,burst index and folding endurance could be improved by 23.0%, 12.7%,63.7%and 115.1%,respectively.