Powdery absorbing material for aqueous liquids based on water-swellable carboxylate polymers

US5229466A · kind A · utility

Assignee

• Chemische Fabrik Stockhausen GmbH · DE

Inventors

• Helmut Brehm · Krefeld, DE
• Richard Mertens · Krefeld, DE

Key dates

• Filing date: May 18, 1992
• Grant date: Jul 20, 1993
• Expiry date: May 18, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F2800/10
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

The present invention relates to a powdery absorbing material for aqueous liquids based on a water-swellable powdery polymer having at least 0.2 equivalents carboxyl groups per 100 parts by weight which are neutralized by 50 to 99, advantageously by at least 80 mole %. The powdery absorbing material is obtained by treating the water-swellable carboxyl-groups-containing polymer with a solution of an N-(hydroxyalkyl).beta.-(meth)-alanine ester or with the polycondensation products thereof. As a solvent for the powdery absorbing material, water is used which either contains water-miscible organic diluents which evaporate on heating, or non-evaporative water-miscible organic diluents, i.e., diluents remaining in the polymer.