【摘要】 以 K2 S2 O8 为引发剂 ,研究了在反相乳液中合成淀粉接枝聚丙烯酰胺共聚物 (S- g- PAM) ,实验证明 ,加入少量铈离子组成复合体系 ,对提高反应速率、接枝率和接枝效率起到显著的促进作用。文中对硫酸铈 -过硫酸钾 (CS-KPS)体系的用量及反应影响因素进行了探讨。更多还原

【Abstract】 The graft copolymerization of acrylamide onto starch was investigated using K 2S 2O 8 as an initiator in inverse emulsion. It was proved that the addition of a little ceric ion, such as CS(ceric sulfate), into the system which formed a complex initiation system played a good rule for high rate of polymerization, high degree of grafting and high grafting efficiency. This article discusses the effects of several factors, such as initiator concentration, monomer concentration, reaction temperature, reaction time and pH on graft copolymerization. Experiments show that degree of grafting and grafting efficiency is the highest when the molar concentration ratio of K 2S 2O 8 to Ce 4+ is about 5∶2, monomer concentration 30 mass%, reaction temperature 45 ℃, reaction time three hours. But pH had little influence on such a reaction. The grafted polymer was confirmed by IR analysis.更多还原