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:
Jul. 05, 1983
Filed:
Jan. 22, 1982
BASF Aktiengesellschaft, , DE;
Abstract
A process for the preparation of polyisobutylene by polymerizing isobutylene in a polymerization zone which is at from 0.degree. to -130.degree. C., by means of from 0.01 to 1.0 percent by weight of boron trifluoride catalyst, in the presence of a primary or secondary alcohol as polymerization accelerator and in the presence of from 30 to 90% by weight of a low-boiling solvent which is inert under the reaction conditions, wherein the solvent vaporized during the polymerization is continuously drawn off, liquefied and recycled, in the liquid state, to the polymerization zone, and wherein the boron trifluoride catalyst used contains less than 0.3, in particular less than 0.01, percent by volume of silicon tetrafluoride and the solvent, which is preferably ethylene, is recycled not less than twice but not more than 36 times during the continuous polymerization.