New telechelic polymers and sequential copolymers by polyfunctional initiator-transfer agents (inifers)

Abstract

α, ω-Di-tert.-chloropolyisobutylenes ($^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{t} } Cl - PIB - Cl^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{t} }$) have been synthesized by the dicumyl chloride/BCl₃ inifer system and the detailed structure of the products has been thoroughly investigated by high resolution ¹³C NMR spectroscopy. To facilitate spectroscopic quantitation the $^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{t} } Cl - PIB - Cl^{\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{t} }$ was dehydrohalogenated to a, α, ω-di(isopropylidene)polyisobutylene (CH₂= C(CH₃)-PIB-C(CH₃)=CH₂). According to this definitive analysis telechelic PIBs with essentially theoretical terminal functionalities (i.e., olefin and by implication tert.-chloro) can be prepared by the inifer technique; evidence for indanyl end groups has not been found. The M_ns of olefin telechelic PIBs can be readily determined by ¹³C NMR spectroscopy.