AlEtCl_(2)/t-BuCl引发α-蒎烯阳离子聚合反应研究

The Cationic Polymerization of α-Pinene with AIEtCl2/ t-BuCl Catalyst

考察了在ＡｌＥｔＣｌ２／ｔ－ＢｕＣｌ引发体系作用下的α－蒎烯阳离子聚合行为．结果表明，ｔ－ＢｕＣｌ与ＡｌＥｔＣｌ２复合后，由于生成（ＣＨ３）Ｃ正离子而使引发活性增大．但ｔ－ＢｕＣｌ的引人对产物分子量及其分布影响不大，产物主要由二、三聚体组成．聚合过程的动力学研究表明，α－蒎烯在进行阳离子聚合时容易发生链终止反应而导致单体转化率和产物分子量较低．α－蒎烯在聚合反应的同时伴随着异构化反应，用制备ＧＰＣ分离出异构化产物，然后经１ＨＮＭＲ测定其结构．

The cationic polymerhation of α-pinene with AIEtCl2/ t--BuCl catalyst was investigated in terms of the action of t-BuCl, the isomerization of monomer, and themolecular weight of products. It was found that the catalystic activity of AIEtCl2 increased due to the formation of (CH3)3C, generated by the reation betweenAlEtCl2 and t-BuCl. The addition of t-Bucl did not affect the molecular weight andmolecular weight distribution (MWD), Low molecule weight oligomers, mostlydimers and trimers, were obtained whether by AlEtCl2 or by AlEtCl2 / t-BuCl. Thekinetic behaviors of polymerzation shown that chain terminations occurred frequentlyin the α-pinene polymerization system,which made both conversion of monomerand molecular weight of products low. The isomers produced by the isomerhation ofα-pinene were separated by preparative GPC and then characterized by 1H-NMRspectroscopy.