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:
Apr. 26, 1994
Filed:
Aug. 26, 1993
Georg Burkhart, Essen, DE;
Rolf-Dieter Langenhagen, Hattingen-Niederwenigern, DE;
Andreas Weier, Essen, DE;
Volker Zellmer, Bottrop, DE;
Th. Goldschmidt AG, Essen, DE;
Abstract
Polysiloxane-polyoxyalkylene block copolymers having different polyoxyalkylene blocks in the average molecule are prepared. The mixture of the polyoxyalkylene blocks consists of at least one polyoxyalkylene group A and at least one polyoxyalkylene group B and/or at least one polyoxyalkylene group C, each polyoxyalkylene group A having an average molecular weight of 600 to 5,500 and consisting of 20 to 90% by weight of oxyethylene units and 80 to 10% by weight of oxypropylene units, polyoxyalkylene group B having an average molecular weight of 500 to 5,000 and consisting of 2 to 19% by weight of oxyethylene units and 98 to 81% by weight of oxypropylene units, polyoxyalkylene group C having an average molecular weight of 1,500 to 4,500 and consisting of oxypropylene units. Up to 20% by weight of the oxypropylene units is replaceable by oxybutylene units and the molar ratio of polyoxyalkylene groups A to the sum of the polyoxyalkylene groups B and C is 1:4 to 4:1. The block copolymers are highly effective stabilizers for the production of flexible polyurethane foams with an excellent ratio of cell fineness of the foam to air permeability of the foam.