Study on synthetic technics of high molecule weight of cationic polyacrylamide

Cationic polyacrylamides based on acrylami(AM) and dimethyldiallylammonium chloride(DMDAAC) have been synthesized in aqueous solution.The effect of dosage of initiator,temperature,the ratio of AM to DMDAAC,pH value on the intrinsic viscosity,cationic degree and relative mass of molecule were studied by orthogonal test.The result indicates that when the temperature is 70 ℃,pH value is 8,the dosage of initiator is 4 mL and DMDAAC/AM is 1∶ 1,the mass of relative molecule is the highest one.At the same time,through the flocculation experiments of using the cationic polyacrylamides synthesized disposing of the model bentonite suspension,the cationic polyacrylamide which the mass of relative molecule 1.73×106 is the best flocculant.It can make the turbidity for 22.4 of the bentonite suspension decline to 3.18,using 0.4 mL of the aqua of 0.05% CPAM and the removal rates of turbidity is 85.80%.