Patent ID: 7947771
Filing Date: 2011-05-24
Classification: A61L,C08F,C08J

Abstract:
1. A process for producing water-absorbing polymers by polymerization of a mixture of a) at least one ethylenically unsaturated acid-functional monomer, each optionally at least partly neutralized, b) at least one crosslinker, c) optionally one or more ethylenically and/or allylically unsaturated monomer copolymerizable with a), and d) optionally one or more water-soluble polymer, optionally at least partially grafted with the monomers a), b), and c), the resulting base polymer A being aftertreated with e) at least one postcrosslinker, the process comprising adding to said mixture, before or during polymerization, at least one water-insoluble metal sulfate in an amount of from 0.001% to 3% by weight based on the water-absorbing polymer produced.