液体聚丁二烯的研制——Ⅲ.不同芳烃链转移剂对聚合反应的影响

SYNTHESIS OF LIQUID POLYBUTADIENE Ⅲ. EFFECTS OF DIFFERENT AROMATJCN HYDROCARBO CHAIN TRANSFER AGENTS ON THE POLYMERIZATION

以正丁基锂-烷氧基钾-二乙二醇二甲醚为引发体系合成液体聚丁二烯,考察了以甲苯及邻、间、对二甲苯和乙苯作链转移剂(兼作溶剂)对调聚反应的影响。实验获得了表现增长速度常数、增长活化能,并考察了它们对丁二烯调聚物分子量的影响,同时得到了在一定条件下的链转移常数、链转移速度常数和转移活化能,测得了在相同条件下的链转移次数。不同芳烃链转移剂对调聚物的微观结构有一定影响。

The synthesis of liquid polybutadiene was studied by using n-butyllithu-mdiglycoldimethylether-potassium alkalioxides as initator system.The effect of toluene, o-xylene, m-xylene, p-xylene and ethylbenzene as solvent and chain transfer agent on telomerization of butadiene were investigated.The apparent rate constant and the activation energy for propagation, the constant of chain transfer, the apparent rate constant of chain transfer, the activation energy of chain transfer and the times of chain transfre were obtained.The results show that different aromatic chain transfer agents have effect on molecular weight but no effect on microstructure and molecular weight distribution of telomer.