摘要
研究了以环己烷为溶剂、正丁基锂为引发剂，异戊二烯阴离子聚合微观结构随ＴＨＦ极性调节剂用量的变化情况。结果表明：（１）异戊二烯在非极性溶剂中聚合时，所得产物的３，４－结构含量较低，仅为５％～８％；１，４－结构含量为９２％～９５％；（２）随ＴＨＦ用量的增加，３，４－结构含量逐渐增加，并且当Ｒ≥１２时，会出现１，２－结构，其变化趋势也是随ＴＨＦ用量增加而增加。根据以上结果，并以金关泰、李天虎的丁二烯阴离子聚合机理［１］为基础，提出了适用于异戊二烯阴离子聚合的σ－烯丙基型，π－烯丙基型活性中心的聚合机理；同时用公式ｌｇ（ａ－ｂａ－Ｉｖ－１）＝ｎｌｇ［ＴＨＦ］＋ｌｇＫ′对所得微观结构数据进行处理，结果线性关系很好，从而验证了机理的正确性。
his paper deals with the relationship between the microstructures of PIp and the concentration of THF with cyclohexane as solvent,n-BuLi as initiator.The results showed that in nonpolar solvent,3,4-contents in PIp was about 5%～8%and 1,4-contents was about 92%～95%;3,4-contents increased gradually with the increase of ,in addition,when the molar ratio of toexceede certain value,1,2-structure would appear;finally,based on the revised σ-、π-allyl mechanismand the experimental results mentioned above a proper mechanism available to the anionic polymerization of isoprene was proposed,and further verified by equation lg(a-ba-Iv-1)=nlg+lgK′.
出处
《弹性体》
CAS
1998年第2期12-16,共5页
China Elastomerics
基金
中国石油化工总公司科技开发中心资助
关键词
异戊二烯
阴离子聚合
聚合机理
isoprene
anionic polymerization
polymerization mechanism
