Investigation of the Ticl4 Reaction Order in Living Isobutylene Polymerizations
The reaction order with respect to TiCl4 was investigated in the living polymerization of isobutylene (IB) initiated by 2-chloro-2,4,4-trimethylpentane (TMPCl)/TiCl4 in hexane/methyl chloride (Hx/MeCl) 60/40 v/v cosolvents at −80 °C. It was found that the reaction is more complex than previously believed. The TiCl4 order was found to be closer to 1 at [TMPCl]0 > [TiCl4]0, and closer to 2 when [TMPCl]0 < [TiCl4]0. Kinetic complexity is demonstrated by the fraction order in TiCl4, and the rate-acceleration found when [TMPCl]0 ≫ [TiCl4]0. A comprehensive mechanistic scheme to explain the kinetic behavior of living IB polymerizations is proposed. Further, a new fiber optic mid-IR monitoring method for more convenient kinetic investigations is demonstrated.
Puskas, Judit and Lanzendörfer, M. G., "Investigation of the Ticl4 Reaction Order in Living Isobutylene Polymerizations" (1998). Chemical and Biomolecular Engineering Faculty Research. 519.