Cationic oligomerization of isobutylene oxide

Dioxolane type dimer and trioxane type trimer were the principal product in the cationic polymerization of isobutylene oxide at room temperature. At low temperature polymer formation accompanied by dioxane type dimer through back-biting reaction was predominant. At room temperature, hydride transfer occurs easily to form isomerized oligomers. The effect of solvents and initiators was discussed in correlation with the mechanism.