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:
Mar. 12, 2002
Filed:
Oct. 17, 2000
Applicant:
Inventors:
Suri Narayan Dorai, Owings Mills, MD (US);
Richard Edward Ernst, Kennett Square, PA (US);
Assignee:
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C 4/311 ;
U.S. Cl.
CPC ...
C07C 4/311 ;
Abstract
A process for producing a poly(tetramethylene ether) glycol (PTMEG) or copolymer having a narrowed molecular weight ratio of 1.9 to 2.07 and a dispersity of 1.2 to 1.65 from a starting PTMEG or copolymer with a broader molecular weight distribution having a dispersity of 1.9 to 2.3 and a molecular weight ratio of 2.3 to 2.6 is provided by feeding the PTMEG or copolymer and an effective amount of an inert solvent to a stripping apparatus and stripping at a temperature of 150 to 220 degrees C. and a pressure of 0.5 to 5 mm of mercury.