2D-INADEQUATE Structural Assignment of Polybutene Oligomers

Recent advances in catalytic chain transfer polymerization of isobutylene: a review

This review presents the development of highly reactive polyisobutylene (HRPIB), a major commercial intermediate toward fuel and lubricant additives. Recent years have witnessed very substantial advances in the catalytic chain transfer polymerization (CCTP) of isobutylene/industrial Raffinate-1 (C4 Raffinate) to produce HRPIB, particularly in nonpolar solvents at elevated temperatures. The main subjects of this review are cationic polymerization of isobutylene, progress in HRPIB research and existing challenges, and recent advances of CCTP. New initiating/catalyst systems based on ionic liquids with Lewis acids are detailed, and this approach may open new views in the synthesis of HRPIB. Some current developments in CCTP of industrial Raffinate-1 and mechanistic studies are also described. This review strongly supports that the hydrocarbon soluble Lewis acid·ether (LA·ether) complex catalyzed CCTP will become the most popular technique for preparing HRPIB and could replace the traditional BF₃ catalyzed industrial method.

This review presents the development of highly reactive polyisobutylene (HRPIB), a major commercial intermediate toward fuel and lubricant additives.

Effects of Ether on the Cationic Polymerization of Isobutylene Catalyzed by AlCl3

In this work, we prepared different initiator solutions containing ether and AlCl₃ by changing the addition sequence of ingredients, studied the interactions between ether and AlCl₃ from the evolution of the Fourier transform infrared (FTIR) spectra by comparison, and investigated the catalytic performances of AlCl₃ affected by ether for isobutylene polymerization. We observed that different preparation methods of initiator solutions could lead to two kinds of interactions between ether and H₂O/AlCl₃ in hexane. The strong interaction could stabilize carbenium ions and seriously decrease the catalytic performance, whereas the weak interaction could promote isomerization and proton elimination. Moreover, we found that the preparation method of initiator solutions was not a critical factor in CH₂Cl₂. Finally, a universal mechanism based on the AlCl₃-involved interactions in different solvents was proposed to understand the effects of ether on the cationic polymerization catalyzed by AlCl₃ thoroughly.

Micromixing enhanced synthesis of HRPIBs catalyzed by EADC/bis(2-chloroethyl)ether complex

Better mixing could produce more active centers to accelerate the polymerization by promoting the consumption of carbonium ions.

Fast flow synthesis of highly reactive polyisobutylene co-initiated by an AlCl3/isopropyl ether complex

In this work, with AlCl₃ addition in the range from 4 to 10 mmol L⁻¹ and enough isopropyl ether (ⁱPr₂O) addition, we successfully synthesized highly reactive polyisobutylene (HRPIB) using a microflow system within 12 s or less.

Recent progress in the Lewis acid co-initiated cationic polymerization of isobutylene and 1,3-dienes

This article reviews recent approaches towards the synthesis of exo-olefin terminated polyisobutylenes and well-defined poly(1,3-diene)s based on their scientific and industrial relevance.