| The process of preparing the poly dimethyl diallyl ammonium chloride (DMDAAC) -acrylamide(AM) with cationicity of 30% was studied in this paper. Using monomer DMDAAC and AM as raw material, ammonium persulfate(APS)/sodium bisulfate(RH) redox complex or ammonium persulfate /azobisisobutyronitrile(AIBN) complex as initiators respectively, the polymerization was carried out in the aqueous solution.Based on the present research results of preparing PDA with 30% cationicity, a primary optimization of three factors(initiator concentration, monomer concentration, reaction temperature) was conducted first, while APS/RH was used as initiator, DMDAAC without simply refining was used as raw material. Through a series of orthonormal experiments based on using Na4EDTA as additive, a products with intrinsic viscosity 8.65 dL·g-1, the percent of the residual double bond 25.65% and its preparation condition were obtained.At the same time, a primary study of preparing PDA with 30% cationicity was made on the basis of using ammonium persulfate/ azobisisobutyronitrile complex as initiator. Through a series of orthonormal experiments in the first stage and the single factor experiments in the second stage, a product with intrinsic viscosity 8.98 dL·g-1 and percent of the residual double bond 26.5%, and its preparation condition were obtained.The result showed that the percent of the residual double bond could be reduced effectively by using Na4EDTA as additive and the preparation processes stability was increased. The percent of the residual double bond could be reduced and the intrinsic viscosity could be increased also, by using APS-AIBN complex as initiator. The results in this paper would have a guiding function on the preparation of PDA with cationicity of 30% in the future. |
