Synthesis and Characterization of Polyisobutylene-Polybutadiene Diblocks

Abstract
The synthesis and characterization of novel polyisobutylene-poly-butadiene diblocks (PIB-b-PBd) are described. The total synthesis involves two steps: 1) The synthesis of t-chlorine terminated PIB (PIB-CH2C(CH3)2CI, PIB-CIt) and 2) the one-pot dehydrochlori-nation-metalation of PIB-CIt by n-BuLi/t-ROK system (where t-R = t-butyl, t-amyl) to the PIB‒CH2C(=CH2) CH- 2, (PIB-) anion followed by initiation of butadiene (Bd) polymerization by the macroanion. Detailed characterization studies including 13H- and 13C-NMR spectroscopies, GPC, fractional precipitation, and model compound studies conclusively prove the synthesis of the PIB-b-PBd diblocks with ∼ 60% 1,2 and ∼ 40% 1,4 PBd microstructure.