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:
Feb. 21, 1995
Filed:
May. 17, 1993
Georg Burkhart, Essen, DE;
Dietmar Schaefer, Hattingen, DE;
Andreas Weier, Essen, DE;
Dietmar Wewers, Bottrop, DE;
Th. Goldschmidt AG, Essen, DE;
Abstract
Polyether siloxanes, which are linked to the polysiloxane backbone through Si--C bonds, are synthesized by reacting given polysiloxanes with a compound having at least one epoxide group in such amounts, that there are at least two epoxide groups per OH group, in the presence of Lewis acids at temperatures not exceeding 60.degree. C. or in the presence of complex catalysts, which accelerate the addition between epoxide groups and hydroxyl groups, at temperatures up to 140.degree. C., the reaction optionally being carried out in the presence of an inert solvent. The polyether siloxanes obtained have a defined functionality and are free of excess, unreacted polyol components.