CO_2介质中淀粉/丙烯酰胺接枝共聚反应

在CO2的保护下,以淀粉为基材,丙烯酰胺为单体,过硫酸铵/尿素为引发体系,通过水溶液聚合的方法,制备了淀粉接枝丙烯酰胺聚合物絮凝剂,考查了反应温度、反应物配比、引发剂用量和反应时间对接枝共聚物的接枝率、单体转化率以及特性黏数的影响。结果表明,当淀粉与丙烯酰胺质量比为1.0∶1.5、引发剂用量为单体质量的0.4%、60℃反应4 h时接枝率达到最高,为135.8%,此时单体转化率为99.9%,接枝共聚物的特性黏数为951 mL/g。

Graft copolymerization of starch and acrylamide in carbon dioxide medium

The graft copolymer from starch and acrylamide was prepared by solution polymerization reaction with initiator system(ammonium persulfate/urea) under the protection of CO2.The effect of the reaction temperature,the ratio of reactants,initiator content and reaction time on grafting ratio,monomer conversion and characteristic viscosity was studied.Results showed that the best reaction condition is:the quality ratio of starch and acrylamide is 1.0∶1.5,initiator content is 0.4 percent of monomer quality,reaction temperature 60 ℃ and reaction time 4 h and grafting ratio can reach the highest value 135.8%,in which monomer conversion is 99.9%,characteristic viscosity is 951 mL/g.