On the drainage adding and strangthening function of chitosan, DMDAAC and starch graft copolymer

The ternary polymer was prepared from the graft copolymerization of dimethyl diallyl ammonium chloride (DMDAAC), chitosan and soluble starch, which was initiated with cerium ammonium nitrate(CAN) as initiator and its application in papermaking was explored. The paper mainly discussed the influence of the viscosity and surface cationic charge of the graft copolymer on the drainage and strengthening effect and collcoid titration was used to measure the surface charge of graft copolymer and fibrous suspension and the appropriate addition range of the additives was calculated. The reaction system of the most optimal additive was pH value 3.97, reaction temperatrue 95℃, reaction time 2.5h, viscosity 478mPa·s, surface cationic charge 0.883mmol/g. When the charge of the graft copolymer was 0.6%, the breaking length was increased by 16.68%, the tearing index was increased by 35.4% and the bursting index was increased by 12.92%.