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. 01, 1991
Filed:
Jun. 25, 1990
Applicant:
Inventor:
Suriyanarayanan Dorai, Lockport, 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 ; 518621 ;
Abstract
A process for preparing a narrow molecular weight distribution poly(tetramethylene ether) glycol (PTMEG) from a PTMEG starting material via liquid-liquid extraction which employs methanol, water and non-polar solvent wherein the amount of non-polar solvent is, by weight, less than the PTMEG starting material.