A Bibliometric Survey on Polyisobutylene Manufacture

Polyisobutylenes (PIB) constitute a versatile family of polymer materials that have been used mainly as fuel and lubricant additives. Particularly, the current commercial demand for highly reactive polyisobutylene (HR-PIB) products motivates the development of new processes and procedures to produce PIBs with high polymer yields, narrow molar mass distributions and high vinyl contents. For this reason, a bibliometric survey is presented here to map and discuss important technical aspects and technological trends in the field of solution cationic polymerization of isobutylenes. It is shown that investigations in this field are concentrated mainly on developed countries and that industrial initiatives indicate high commercial interest and significant investments in the field. It is also shown that use of catalyst systems based on AlCl3 and ether cocatalysts can be very beneficial for PIB and HR-PIB manufacture. Finally, it is shown that investigations search for cheaper and environmentally friendly catalysts and solvents that can be employed at moderate temperatures, particularly for the production of HR-PIB.

Complexes of aluminum, iron(III), and gallium(III) chlorides with ethers in synthesis of highly reactive polyisobutylene

In this review, the latest achievements in the field of cationic polymerization of isobutylene catalyzed by the complexes of conventional Lewis acids with ethers are presented. The experimental and computational data on the influence of steric structure and basicity of ether used for the preparation of the Lewis acid-ether complex on the catalyst activity and regioselectivity of β-H abstraction are discussed here. Complexes of metal halides with linear (Bu2O) and moderately branched (iPr2O) ethers of moderate basicity (pKa from –4.3 to –5.4) displayed the highest activity and regioselectivity in the cationic polymerization of isobutylene affording highly reactive polyisobutylene (HR PIB) – the key intermediate in the preparation of motor oil and fuel additives. The review is also focusing on the adaptation of the developed catalytic system to the industry, which consists in using non-polar hydrocarbon solvents, high temperatures and monomer concentrations.

Tailoring the AlCl3/iPr2O/Et2O initiation system for highly reactive polyisobutylene synthesis in pure n-hexane

Effective HRPIB synthesis in n-hexane was achieved by tailoring the AlCl3/iPr2O/Et2O initiation system using a novel preparation method.

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.

Synthesis of highly reactive polyisobutylene by catalytic chain transfer in hexanes at elevated temperatures; determination of the kinetic parameters

The rate constants of activation/deactivation for dormant oxonium/active carbenium ions have been measured and related to the increasing polymerization rate with increasing temperature.

New catalysts for the synthesis of highly reactive polyisobutylene: chloroaluminate imidazole-based ionic liquids in the presence of diisopropyl ether

The use of [emim]Cl–AlCl3 in combination with iPr2O allowed the synthesis of HR PIB with high exo-olefin end group content (≥90%) and a relatively narrow MWD (Mw/Mn ≤ 2.0) at a high reaction temperature (>0 °C) and monomer concentration (5.2 M–7.8 M).