阴离子溶聚丁戊橡胶分子量的研究

Study on the molecular weight in anionic copolymerization of butadiene and isoprene

以正丁基锂为引发剂,分别以二氧六环(DOX)和二乙二醇二甲醚(2G)为极性调节剂研究了异戊二烯和丁二烯阴离子共聚物分子量随反应时间的变化规律。实验发现,聚合物的分子量与活性种的活性有关,高温严重破坏活性种的活性,调节剂用量是杀死活性种活性的另一因素。聚合前期,分子量随时间的增加而增大;温度升高后,高温破坏了活性种的活性,活性链解缔合导致的粘度下降,所以聚合后期分子量降低。2G对活性链的破坏受温度的影响要小于DOX受温度的影响。

The molecular weight of the copolymerization product of butadiene and isoprene was studied, with n-BuLi as initiator, and dioxane and diethylene glycol dimethyl ether as modifier. The result showed that high temperature could spoil the activity of reactive species as well as the dosage of polar modifier which is an ther factor to kill reactive species. At the beginning of the reaction, the molecular weight increased with the time increased. High temperature killed the activity of reactive species with the temperature increased, so the viscosity and molecular weight decreased at the latter reaction. The influence of the temperature on the extermination of 2G to reactive species was less than it of DOX.