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:
Jan. 21, 1997
Filed:
Dec. 22, 1995
Peter A Bloxham, Houston, TX (US);
Anne I Breikss, Hockessin, DE (US);
Richard E Ernst, Kennett Square, PA (US);
Leon S Scott, Wilmington, DE (US);
John D Super, Wilmington, DE (US);
James D Verbsky, Seabrook, TX (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process for removing precursors, such as low boiling alkyl glycols (e.g., ethylene glycol and/or 1,2-propylene glycol), to undersirable color forming acetal impurities (e.g., 1,3 -dioxolane and 4-methyl-1,3-dioxolane) from technical grade 1,4-butanediol/2-methyl-1,4-butanediol mixtures and the like by distillative topping of the diol mixture prior to ring closing cyclization to corresponding tetrahydrofuran/3-methyl tetrahydrofuran mixture and subsequent polymerization to polytetramethylene glycol ether polymers. Such a process is useful to produce THF and PTMEG having a APHA color index of nearly zero.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile