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:
Aug. 04, 2026
Filed:
Jul. 02, 2021
Evonik Operations Gmbh, Essen, DE;
Jens Hildebrand, Johannesberg, DE;
Annegret Terheiden, Alpen, DE;
Natalia Hinrichs-Tontrup, Alzenau, DE;
Walter Pfefferle, Langgoens, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
The present invention relates to an improved process for depolymerization of polyurethanes under mild conditions, wherein polyether polyols and polyamines can be recovered in high yields. The method is practiced by hydrolyzing a polyurethane by contacting with water in the presence of a base containing an alkali metal cation and/or an ammonium cation and having a pKvalue at 25° C. of from 1 to 10 and a catalyst selected from the group consisting of quaternary ammonium salts containing an ammonium cation containing 6 to 30 carbon atoms and organic sulfonates containing at least 7 carbon atoms to yield an active hydrogen containing polyether.