双金属氧联醇盐催化环硫丙烷的开环聚合

研究了环硫丙烷以铝锌双金属氧联醇盐为催化剂在甲苯中的聚合动力学及分子量分布。结果表明,环硫丙烷的聚合速度对单体浓度是二级关系,对催化剂浓度是半级关系。聚合系统中催化剂存在缔合,认为环硫丙烷以双分子配位增长。测得聚合活化能为12.2±0.5kcal/mol,计算了单体及溶剂的链转移常数。通过淋洗液中加氯化锂的GPC工作研究了分子量及其分布随转化率的变化。

RING-OPENING POLYMERIZATION OF PROPYLENE SULFIDE CATALYZED BY BIMETALLIC ALKOXIDE

It was shown that the polymerization rate of propylene sulfide is second order with respect to monomer concentration and half order with respect to catalyst concentration. A mechanism of himolecular coordinated propagation of propylene sulfide and association of the catalyst in the polymerization system was proposed. The activation energy of polymerization was measured as 12.2 ± 0.5 kcal/mole. Chain transfer constanst to monomer and solvent were calculated. The change of molecular weight and molecular weight distrbution with conversion was followed by GPC which was improved by ad-ding LiCl to eluant.