Telechelic Polyisobutylenes by 2,5-Dichloro-2,5-dimethyl-3-hexene, Aliphatic Binifers

지방족 비니퍼, 2,5-디클로로-2,5-디메틸-3-헥센을 이용한 텔레킬릭 폴리이소부틸렌의 중합

The synthesis of α, ω-di-tert-chloropolyisobutylens(chlorine-telechelic PIB's) containing ethylene unit at the center of molecule have been carried out at -30℃ in methyl chloride by the use of aliphatic binifers. The aliphatic binifers are cis-and trans-2,5-dichloro-2,5-dimethyl-3-hexenes. The undesirable side reaction, intramolecular cyclization was prevented in this allylic structure containing aliphatic dichloride/BCl3 initiationg system. Well established binifers, i.e., p-dicumyl chloride gives the unacceptable side reaction for perfect terminally functional prepolymer, unless the inifer process is carried out at -80℃. Chain transfer constant to inifer (CI) and kt/kp values were determined and the results show both cis- and transisomers are very effective binifers for the preparation of the biterminally functional PIB, free from aromatic fragment.