Process for the production of a superabsorbent polymer

US8252873B1 · kind B1 · utility

Assignee

• Evonik Stockhausen GmbH · US

Inventors

• Herbert Gartner · Baden-Baden, DE
• Jorg Harren · Baesweiler, DE
• Marc Hager · Bischwiller, FR
• Harald Plochinger · Bühl, DE
• Daniel Fricker · Rœschwoog, FR
• Hans-Peter Kohler · Bühlertal, DE
• Sabine Auernig · Achern, DE

Key dates

• Filing date: Apr 13, 2012
• Grant date: Aug 28, 2012
• Expiry date: Apr 13, 2032

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K5/175
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to superabsorbent polymer comprising the comprising the free radical polymerization product of an aqueous monomer mixture containing at least one α,β-ethylenically unsaturated monomer; at least one monomer having at least two α,β-ethylenically unsaturated groups; a crosslinking agent having at least two polymerizable double bonds; iron ions in an amount of from about 0.1 to about 3 wppm based on the total weight of the aqueous monomer mixture; and at least one chelating agent in an amount to provide a molar ratio of chelating agent to iron ion of from about 0.8 to about 4.0.