Hydrophilic hydrogels with a high swelling capacity and method for producing and using them

US6602950B1 · kind B1 · utility

Assignee

• BASF SE

Inventors

• Joachim Dentler · Bruchköbel, DE
• Rüdiger Funk · Niedernhausen, DE
• Norbert Herfert · Charlotte, US
• Mariola Wanior · Niederrodenbach, DE
• Friedrich Engelhardt · Frankfurt, DE

Key dates

• Filing date: Apr 6, 2001
• Grant date: Aug 5, 2003
• Expiry date: Apr 6, 2021

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S604/904
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A hydrophilic, highly swellable hydrogel based on (co)polymerized monomers or based on graft (co)polymers and prepared bya) free-radically (co)polymerizing one-or more hydrophilic monomers or graft (co)polymerizing one or more hydrophilic monomers onto a grafting base, the average degree of neutralization of the acid-functional monomers being from 0 to 40 mol %,b) comminuting the acidic hydrogel,c) neutralizing the acidic hydrogel to an ultimate degree of neutralization of 50-85 mol % by adding a neutralizing agent,d) drying, grinding and sieving the hydrogel particles characterized bya centrifuge retention and a vertical absorption swell height, each having a specified minimum.value, coupled with an extractables content having a specified maximum value ora centrifuge retention and a vertical absorption swell height, each having a specified minimum value andan extractables content having a specified maximum value.