Patent ID: 8618206
Filing Date: 2013-12-31
Classification: B01J,C08F,C08J

Abstract:
1. A process for producing water-absorbing polymer particles by polymerizing an aqueous monomer solution or suspension comprising a) at least one ethylenically unsaturated monomer which bears an acid group, which has been neutralized to an extent of 70 to 85 mol %, b) at least one crosslinker, c) at least one initiator, d) optionally one or more ethylenically unsaturated monomer copolymerizable with the monomer specified under a), and e) optionally one or more water-soluble polymer, comprising drying a resulting aqueous polymer gel, grinding, classifying and thermal surface postcrosslinking to provide water-absorbing polymer particles, which comprises coating the water-absorbing polymer particles, before, during, or after the surface postcrosslinking, with 0.0001 to 0.25% by weight of silicon dioxide and at least 1.5×10