异丙醇氧锂-正丁基锂-丁二烯负离子聚合体系的研究

Study on Anionic Polymerization of Butadiene Initiated by n-BuLi in the Pres ence of Lithium sec-Propoxide

采用异丙醇和正丁基锂反应制备了异丙醇氧锂,并作为添加剂在环己烷中进行了丁二烯的负离子聚合。随着异丙醇氧锂加入量的增加,聚丁二烯基锂环己烷溶液的粘度下降,活性种的活性也降低;但对聚丁二烯的微观结构影响很小。异丙醇氧锂与丁二烯基锂活性种形成交叉缔合,宏观上表现为聚丁二烯基锂的缔合度降低,活性聚合物溶液粘度下降。

Lithium sec-propoxide was prepared by reaction of 2-propanol and n-BuLi or lithium,and was used as additive in anionic polymerization of butadiene(PB) in cyclohexane.With increasing amount of lithium sec-propoxide,the solution viscosity of polybutadienyllithium decreased gradually and it's activity became low.However,lithium propoxide had little effect on microstructure of PB.Lithium sec-propoxide and polybutadienyllithium formed cross association,leading to dissociation of polybutadienyllithium.