摘要
用AlCl3、TiCl4、BF3OEt2和CF3SO3H在不同溶剂中引发异戊二烯阳离子聚合反应,结果表明,反应条件对聚合物结构有很大影响。AlCl3引发的聚合反应生成不溶性交联产物和可溶聚合物两部分,后者又包含了环状和线型链(主要是1,4和3,4结构单元)两种主要链节,由CF3SO3H引发的聚合反应只生成可溶性聚合物,聚合物链全部由环状结构组成。TiCl4和BF3OEt2引发的聚合反应受反应介质影响较大,在正己烷中有交联产物生成,可溶性聚合物链包含环状结构和线型链,当用极性的二氯甲烷或用甲苯作反应介质时,交联反应得到完全的抑制,且聚合物链的环状结构分数显著增加。
The cationic polymerizations of isoprene initiated by AlCl 3, TiCl 4, BF 3OEt 2 and CF 3SO 3H were carried out in various solvent. The polymer structrue is mainly determined by reaction conditions. The polymerization initiated by AlCl 3 produces both insoluble (crosslinked) and soluble polymers, and the latter contains cyclic and linear (1,4 and 3,4 units) segments. In contrast, the CF 3SO 3H induced polymerization generates only soluble polymer consisting of completely cyclized structure. On the other hand, TiCl 4 and BF 3OEt 2 based polymerizations are heavily influenced by reaction medium. The polymerization in n hexane produces insoluble crosslinked products and soluble polymers made of cyclic and linear structures, and only soluble polymers of highly cyclized structure are formed in methylene chlorides and in toluene.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
1997年第4期95-98,共4页
Polymer Materials Science & Engineering
关键词
异戊二烯
阳离子聚合
链结构
聚合
异丁烯
共聚
isoprene, cationic polyomerization, chain structure, cyclization, crosslinking