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:
Oct. 14, 2014
Filed:
Oct. 05, 2011
Christoph Loick, Tonisvorst, DE;
Dominik Gartz, Viersen, DE;
Laurent Wattebled, Dusseldorf, DE;
Jorg Harren, Baesweiler, DE;
Christoph Loick, Tonisvorst, DE;
Dominik Gartz, Viersen, DE;
Laurent Wattebled, Dusseldorf, DE;
Jorg Harren, Baesweiler, DE;
Evonik Degussa GmbH, Essen, DE;
Abstract
A process for producing a water-absorbing polymer comprises: (i) mixing (α1) 0.1-99.99% by weight of ethylenically unsaturated monomers containing acid groups or salts thereof, or ethylenically unsaturated monomers including a protonated or quaternized nitrogen, or mixtures thereof, (α2) 0-70% by weight of ethylenically unsaturated monomers copolymerizable with (α1), (α3) 0.001-10% by weight of one or more crosslinkers, (α4) 0-30% by weight of water-soluble polymers, and (α5) 0-20% by weight of one or more assistants, where the sum of the weights (α1) to (α5) is 100%; (ii) free-radical polymerization with crosslinking to form an untreated hydrogel polymer; (iii) coarse comminution of the untreated hydrogel polymer to give pieces having a diameter from 0.1 mm to 5.0 cm; (iv) cooling and grinding the untreated hydrogel polymer; (v) drying the untreated hydrogel polymer after grinding at a temperature from 85° C. to 260° C.; (vi) postcrosslinking the hydrogel polymer and (vii) drying the water-absorbing polymer.