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:
Aug. 29, 1995
Filed:
Nov. 10, 1993
Ronald J Hoxmeier, Houston, TX (US);
Bridget A Spence, Houston, TX (US);
Steven S Chin, Houston, TX (US);
Michael A Masse, Richmond, TX (US);
Shell Oil Company, Houston, TX (US);
Abstract
A process is disclosed for producing six-armed and eight-armed asymmetric radial block copolymers. The process comprises anionically polymerizing a diene and/or a vinyl aromatic hydrocarbon to create living polydiene and/or vinyl aromatic hydrocarbon arms, sequentially anionically polymerizing a vinyl aromatic hydrocarbon and a diene to create living block copolymer arms and coupling the two sets of arms together in one step with a coupling agent that will couple six or eight arms, wherein the molar ratio of the vinyl aromatic hydrocarbon-diene arms to the polydiene arms is sufficient to produce a statistical blend with less than 5 weight percent homopolydiene.