Synthesis of a cationic polyacrylamide with high molecular weight and high purity
高分子量高纯度阳离子聚丙烯酰胺的合成

In this research,a cationic polyacrylamide(CPAM) with high molecular weight and high purity was synthesized though aqueous copolymerization of acrylamide with acryloyloxyethyltrimethyl ammonium chloride,and the composite initiators were used to accelerate the polymerization.The experimental results showed that the molecular weight of CPAM with a high solubility in the range of 10.42 million was achieved when azo initiator(A) dosage was 0.5‰,redox initiator dosage was 0.45‰,the reducer/oxidizer molar ratio was 2∶ 1,reaction time was 5 h,and pH was 4.In addition,some parameters affecting residual monomer concentration such as additive concentration and reaction time were examined.The results indicated that additives(EDTA and solubilizer D) had no significant influence on the concentration of the residual AM monomer but sodium benzoate exhibited a remarkable effect on the AM concentration.Consequently,when prolonging the reaction time to 7 hours,the residual monomer concentration would be reduced to 0.27%,and a high purity CPAM was obtained.By compared with three same type products made at home and abroad,it showed that the molecular weight of CPAM was significantly higher than other products,and the residual content of AM was lower than domestic products,with a single reduction of 50%~75%.