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:
Jun. 02, 1992
Filed:
Feb. 13, 1991
Applicant:
Inventors:
Suriyanarayan Dorai, Lockport, NY (US);
Gerfried Pruckmayr, Media, PA (US);
Marianne Marsi, Wilmington, DE (US);
Willard L Quon, East Amherst, NY (US);
Assignee:
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
568617 ;
Abstract
A catalyst and process for preparing it and its use in polymerizing tetrahydrofuran to produce polytetramethylene ether glycol ether are disclosed. The catalyst is a blend of a fluorinated resin containing sulfonic acid groups and a fluorinated resin containing carboxylic acid groups. The catalyst is partially dried to contain from 1,000 to 2,000 ppm water, so that when it is used to polymerize tetrahydrofuran, the product polytetramethylene ether glycol will have a number average molecular weight of from 250 to 4,000.