【摘要】 以BPO为引发剂,甲苯为溶剂,采用溶液聚合法合成了低 3 异丙烯基 α,α′ 二甲基苄基 异氰酸酯(TMI)含量的PSt TMI共聚物(wTMI =0.03~0.11),确定了 FTIR方法测定共聚物中 TMI含量的方法,并对反应动力学与共聚物组成进行了研究。结果表明:总体反应速率与单体浓度成正比,与引发剂浓度 0.5 次方成正比,80℃下反应时还存在热引发,终止方式为双基终止;反应总体活化能随单体配比中 TMI分率增大而升高。引发剂浓度增大则产物分子量减小,分子量分布不变。随反应转化率提高分子量分布指数增大、产物中TMI含量略有下降。GPC串联紫外分析表明,产物中高分子量部分 TMI 含量高于低分子量部分中TMI含量。更多还原

【Abstract】 The kinetics of copolymerization of styrene and 3-isopropenyl-α,α′-dimethylbenzyl isocyanate(TMI) with toluene as solvent and dibenzoyl peroxide(BPO) as initiator was studied. The composition of copolymer was checked by FTIR. The study indicated that the overall rate of polymerization is in direct proportion to the concentration of overall monomer and also in direct proportion to the square root of the concentration of the initiator. And the copolymerization is diradical-termination with thermal initiaton. The overall activation energy grows with the increase of the ratio between TMI/St. More initiator results in grow of polymerization rate and decrease of molecular weight. GPC analysis indicated that the content of TMI in copolymer with higher degree of polymerization is larger in those with lower degree of polymerization.更多还原