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:
Oct. 28, 1980
Filed:
Jan. 31, 1979
Robert T Prudence, Akron, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
There is disclosed a process for the preparation of medium vinyl polybutadiene which comprises copolymerizing butadiene with small amounts of divinylbenzene in a hydrocarbon solvent system employing as a catalyst an alkyl lithium compound which has been modified by mixtures of polar compounds, at least one of which polar compound is selected from the group consisting of hexamethylphosphoric acid triamide (HMPA), N,N,N'N'-tetramethylethylene diamine (TMEDA), ethylene glycol dimethyl ether (glyme), diethylene glycol dimethyl ether (diglyme), triethylene glycol dimethyl ether (triglyme) and tetraethylene glycol dimethyl ether (tetraglyme), and at least one of which polar compound is selected from the group consisting of tetrahydrofuran (THF), 1,4diazabicyclo [2.2.2] octane (DABCO), diethyl ether, triethylamine, tri-n-butylamine, tri-n-butylphosphine and p-dioxane, in which the temperature is maintained constant throughout the polymerization.