Process for the preparation of a hydrogel which is largely free from monomers

US4794166A · kind A · utility

Assignee

• Cassella Aktiengesellschaft · DE

Inventors

• Friedrich Engelhardt · Frankfurt, DE
• Manfred Schrod · Weiterstadt, DE
• Manfred Ziegelmayer · Bischofsheim, DE
• Josef Hilbig · Taunusstein, DE
• Reinhard Donges · Bad Soden, DE

Key dates

• Filing date: Jul 27, 1987
• Grant date: Dec 27, 1988
• Expiry date: Jul 27, 2007

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S524/916
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A polymer hydrogel substantially free from monomers and oligomers is prepared by contacting a previously prepared polymer hydrogel with a single-phase mixture of water and a solvent and then separating the mixture of water and solvent from the hydrogel.