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:
Nov. 15, 1983
Filed:
Mar. 25, 1982
Sunil B Sarkar, Akron, OH (US);
The Firestone Tire & Rubber Company, Akron, OH (US);
Abstract
A method for preparing essentially color-free, stabilized polymers of conjugated dienes or vinyl aromatic hydrocarbons or copolymers of conjugated dienes and vinyl aromatic hydrocarbons involves a first stage in which a living polymer of a conjugated diene or vinyl aromatic hydrocarbon or copolymer of a conjugated diene and a vinyl aromatic hydrocarbon is prepared by anionically polymerizing the conjugated diene or vinyl aromatic hydrocarbon, or copolymerizing the conjugated diene and the vinyl aromatic hydrocarbon using a lithium-based catalyst and an inert hydrocarbon diluent. Then, the living polymer or copolymer is terminated by the addition of a suitable terminating agent. Following the termination procedure, boric acid is added to the polymer of copolymer in a sufficient amount to prevent or substantially reduce color formation. Then, stabilizing agents are added to the polymer or copolymer and the polymer or copolymer is recovered from the diluent.