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. 10, 1981
Filed:
Mar. 03, 1980
Tristram W Bethea, Wadsworth, OH (US);
Shingo Futamura, Wadsworth, OH (US);
The Firestone Tire & Rubber Company, Akron, OH (US);
Abstract
A method for increasing the primary hydroxyl end groups in polyethers includes the steps of charging a reaction vessel with tetrahydrofuran and propylene oxide, adding BF.sub.3 or a BF.sub.3 -containing catalyst and then polymerizing the first pair of monomers to form a copolymer. After the first copolymerization is at least 60 percent complete, the method further includes the steps of adding ethylene oxide to the copolymer and unreacted monomers in the reaction vessel, and polymerizing the contents therein to form a terpolymer predominantly terminated by primary hydroxyl groups. The reaction is thereafter terminated and the terpolymer is separated from the remaining contents of the reaction vessel, washed and dried. The resulting terpolymer has from about 20 to about 80 weight percent of tetrahydrofuran, from about 10 to about 60 weight percent of propylene oxide, from about five to about 40 weight percent of ethylene oxide and at least 60 mole percent of terminal primary hydroxyl groups.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile