The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 18, 2000
Filed:
Jun. 30, 1997
Gerhard Langstein, Kurten, DE;
Martin Bohnenpoll, Leverkusen, DE;
Uwe Denninger, Bergisch Gladbach, DE;
Werner Obrecht, Moers, DE;
Peter Plesch, North Staffordshire, GB;
Bayer AG, , DE;
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.