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:
May. 11, 2021
Filed:
Apr. 29, 2014
Evonik Operations Gmbh, Essen, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
The present invention relates to a process for producing a water-absorbing polymer, comprising the process steps of (i) mixing (α1) 0.1 to 99.999% by weight of polymerizable, ethylenically unsaturated monomers containing acid groups, or salts thereof, (α2) 0 to 70% by weight of polymerized, ethylenically unsaturated monomers copolymerizable with (α1), (α3) 0.001 to 10% by weight of one or more crosslinkers, where the sum of the weights (α1) to (α3) is 100% by weight, (ii) free-radical polymerization with crosslinking to form a water-insoluble, aqueous untreated hydrogel polymer, (iii) drying the hydrogel polymer, (iv) grinding and sieving the water-absorbing polymer to size, wherein the aqueous monomer solution, is admixed with 0.01 to 5% by weight of at least one surfactant and optionally 0.01 to 5% by weight of a blowing agent having a particle size of 10 μm to 900 μm, based on the water-absorbing polymer.