Mechanism of Isomerization in the Cationic Polymerization of Isobutylene

The complex mechanism of the carbocationic rearrangements leading to a variety of olefin (exo-, endo-, tri-, and tetra-substituted) end groups in the cationic polymerization of isobutylene (IB) catalyzed by ethylaluminum dichloride (EtAlCl2) in nonpolar solvents in the temperature range of −40 to 25 °C was studied by model ionization experiments employing poly(isobutylene chloride) (PIB-Cl) of low molecular weight (Mn ∼ 1000−2000) obtained by...