Initiator systems containing vanadium tetrachloride for the (co)polymerization of isoolefins

US6015841A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gerhard Langstein · Kürten, DE
• Martin Bohnenpoll · Cologne, DE
• Uwe Denninger · Bensberg, DE
• Werner Obrecht · Moers, DE
• Peter Plesch · Stafford, GB

Key dates

• Filing date: Jun 30, 1997
• Grant date: Jan 18, 2000
• Expiry date: Jun 30, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F210/12
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

This invention relates to an initiator system for the polymerization of isoolefins having 4 to 16 carbon atoms, optionally with monomers polymerizable with isoolefins, the system consisting of or one or more aromatic or heteroaromatic, polycyclic hydrocarbons and an aged, organic solution of vanadium tetrachloride, wherein the concentration of the vanadium tetrachloride is 0.01 mmol to 500 mmol per liter of solvent and the molar ratio of aged vanadium tetrachloride to polycyclic hydrocarbons is in the range from 100:1 to 1:100. It is possible by means of the initiator system according to the invention to produce polyisoolefins, in particular butyl rubbers, at relatively high temperatures with only a low gel content and of a sufficiently high molecular weight.