.80%, 90% Of The Cationic Degree Of Pda Preparation Process Is A Preliminary Study

The process of preparing poly DMDAAC-AM(PDA)was studied in this paper.Using acrylamide(AM)and dimethyldiallylammonium chloride(DMDAAC)as raw materials and ammonium persulfate(APS)as initiator,PDA copolymers with cationicity of 80%and 90%were synthesized by aqueous solution polymerization and the method of adding all raw materials in one step.Based on present polymerization process of poly-DMDAAC in our research group,the effects of various factors such as monomer concentration,the amount of initiator and Na₄EDTA and temperatures were researched respectively.The optimal conditions of synthesizing PDA with cationicity of 80%and 90%were obtained via a series of preliminary and orthonormal experiments.The optimal processing conditions of PDA with cationicity of 90%were:m(DMDAAC and AM)%=67.5%, w(APS):w(DMDAAC and AM)=0.020%,w(Na₄EDTA):w(DMDAAC and AM)=0.0066%, and the copolymerization was carried out by maintaining the reaction temperature of 40℃,53℃,75℃each for 3 hours,the highest value of intrinsic viscosity was 3.90dL·g^-1 and its correspongding residual double bond percent was 4.3 1%.The optimal processing conditions of PDA with cationicity of 80%were:m(DMDAAC and AM)%=65.0%, w(APS):w(DMDAAC and AM)=0.015%,w(Na₄EDTA):w(DMDAAC and AM)=0.0139%, and the copolymerization was carried out by maintaining the reaction temperature of 40℃,50℃,75℃each for 3 hours,the highest value of intrinsic viscosity was 4.12dL·g^-1 and its correspongding residual double bond percent was 7.98%.Meanwhile,on the basis of the optimal processing conditions,the factors which affected the product intrinsic viscosity were studied respectively.The studies of the preparation of PDA with high intrinsic viscosity could enrich the recognization of process in preparing PDA theoritically and be a good foundation for its further mechanism researches and industrial production.