Absorbent polymer structure with improved retention capacity and permeability

US7833624B2 · kind B2 · utility

Assignee

• Evonik Stockhuasen GmbH · DE

Inventors

• Jorg Harren · Baesweiler, DE
• Helmut Brehm · Krefeld, DE
• Andreas Kerkmann · Goch, DE
• Stephan Ramlow · Krefeld, DE

Key dates

• Filing date: Oct 24, 2003
• Grant date: Nov 16, 2010
• Expiry date: Sep 24, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31504
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for producing an absorbent polymer structure (Pa) by treating the outer portion of an untreated absorbent polymer structure (Pu1). The process includes the step of bringing the outer portion of the untreated absorbent polymer structure (Pu1) into contact with an aqueous solution including at least one chemical cross-linker and at least one inorganic compound in dispersed colloidal form. The process also includes the step of heating the absorbent polymer structure, of which the outer portion has been brought into contact with the aqueous solution, at a temperature within a range from about 40 to about 300° C., so that the outer portion of the absorbent polymer structure is more strongly cross-linked in comparison to the inner portion and the inorganic compound is at least partly immobilized in the outer portion of the absorbent polymer structure.