Water-absorbent, crosslinked polymer based on unsaturated acid, e.g. polyacrylic acid, and containing alkali silicate, used e.g. in sanitary articles or packaging and especially as a soil improver

摘要

Water and aqueous liquid-absorbent, crosslinked polymers (I) derived from 55-99.9 wt.% unsaturated monomer with acid groups (or its alkali salts), 0-30 wt.% water-soluble polymer and less than 5 wt.% crosslinker, also contains 1-5, preferably 1-3 wt.% alkali silicate, calculated as silicon dioxide and based on the dried product. Independent claims are also included for: (1) process 1, a method for the production of (I) by adding alkali silicate (II) in the form of powder and/or aqueous solution before or during the production or processing of the polymer; (2) process 2, a method for the production of (I) by adding an aqueous solution of (II) to the undried and pulverised polymer product after polymerisation of the aqueous monomer solution and then drying or compounding the product; (3) process 3, a method for the production of (I) by application of an aqueous solution of (II) to the dried, milled and optionally crosslinked polymer followed by drying or compounding; and (4) application of (II) in the form of an aqueous solution by dipping, wetting or spraying the pulverised polymer.