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. 14, 1992
Filed:
Mar. 27, 1991
Applicant:
Inventors:
Suriyanarayan Dorai, Lockport, NY (US);
Willard L Quon, East Amherst, NY (US);
Kirk M Schall, Ponca City, OK (US);
Gary A Hida, Wilmington, DE (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560200 ; 560198 ; 560204 ; 568617 ;
Abstract
A process for polymerizing tetrahydrofuran using a fluorinated resin containing sulfonic acid groups a trifluoromethane sulfonic acid as catalyst and a mixture of maleic acid and maleic anhydride as weight control agent. The product has the formula ##STR1## which can be hydrogenated to produce polytetramethylene ether glycol. The preferred molecular weight range of the polytetramethylene ether glycol is 600 to 4,000.