Synthesis of amphoteric copolymerric flocculant grafted on starch

This paper reports the investigation of the synthesis condition of amphoteric monomer and the rule of copolymerized grafting it on starch by using (NH4)2S2O8 as initiator. Experimental results indicate that the yield of amphoteric monomer is more than 98% under the condition: pH, 9～10;reaction temperature, 85?℃; reaction time, 5?h. The optimum variables of grafting ratio, grafting efficiency, and ［η］ of the copolymer are obtained at initiator concentration of 2.2?mmol/L,monomer dosage of 1.8/1(monomer/starch ),reaction temperature of 45?℃, and reaction time of 4?h.