碳酸乙烯酯溶剂中丙烯腈的聚合行为

以碳酸乙烯酯为溶剂，偶氮二异丁腈（AIBN）为引发剂,采用溶液自由基聚合的方法对丙烯腈(AN)均聚合、丙烯腈/衣康酸(AN/IA)二元共聚及丙烯腈/衣康酸/丙烯酸甲酯(AN/IA/MA)三元共聚合进行了研究。 考察了反应温度对丙烯腈均聚合，以及聚合单体浓度对丙烯腈共聚合的影响，在60 ℃合成了相对分子质量高于4.5×105、单体转化率高于85%的丙烯腈均聚物及共聚物。 采用正十二烷基硫醇（DDT）和甲酰基哌啶（FP）作为链转移剂，对AN均聚物、AN/IA及AN/IA/MA共聚物的相对分子质量进行调控，考察了链转移剂浓度对聚合物相对分子质量和单体转化率的影响。 结果表明，w(DDT)为0.25%时（以单体质量计），聚合物相对分子质量可有效调节到1×105,而单体转化率保持在80%以上。

Acrylonitrile Polymerization Behavior in the Ethylene Carbonate

An homopolymer and acrylonitrile/itaconic acid(AN/IA) bipolymer and AN/IA/MA(methacrylate) terpolymer were prepared in ethylene carbonate(EC) solution using azodiisobutyronitrile(AIBN) as initiator via the free radical solution polymerization method. Effect of reaction temperature on AN homopolymerization and effect of monomer concentration on the copolymerization were investigated. AN copolymer with a relative molecular mass of 4.5×105 and monomer conversion of 85% was synthesized. Relative molecular masses of AN homopolymer, AN/IA and AN/IA/MA copolymers were controlled through N-formylpiperidine(FP) and 1-dodecanethiol(DDT) as chain transfer agents. Influence of the mass fraction of chain transfer agents on the molecular mass and conversion rate of the copolymers were also studied. The results shows that a polymer with molecular mass of 1×105 and monomer conversion of 80% was obtained by 0.25% mass fraction of DDT as chain transfer agent.