Hydrogels absorbing aqueous fluids

US8552071B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Thomas Daniel · Waldsee, DE
• Ulrich Riegel · Landstuhl, DE
• Matthias Weismantel · Bad Orb, DE
• Norbert Herfert · Charlotte, US
• Friedrich Engelhardt · Frankfurt, DE

Key dates

• Filing date: Nov 18, 1999
• Grant date: Oct 8, 2013
• Expiry date: Nov 18, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K3/34
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

The invention relates to hydrogels capable of absorbing aqueous fluids, which hydrogels are produced by polymerization of olefinically unsaturated carboxylic acids or their derivatives. The hydrogels are characterized in that before, during or after the polymerization reaction and before drying a silicic acid alkali salt of the general formula (I) M2O×nSiO2 is added to the polymerization reaction mixture. In said formula M is an alkali metal and n is a number between 0.5 and 4. The hydrogel obtained in this way is then dried at an elevated temperature. The invention also relates to a method for producing said hydrogels and to their use for absorbing aqueous fluids.