Water-absorbing, expanded, crosslinked polymers, the production and use thereof

US6136873A · kind A · utility

Assignee

• BASF SE

Inventors

• Hans-Joachim Hähnle · Neustadt, DE
• Manfred Walter · Nuremberg, DE
• Jurgen Tropsch · Lichtenfels, DE
• Gunnar Schornick · Neuleiningen, DE
• Thomas Anstock · Bad Dürkheim, DE

Key dates

• Filing date: May 4, 1998
• Grant date: Oct 24, 2000
• Expiry date: May 4, 2018

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61L15/60
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

Water-absorbing, expanded, crosslinked polymers obtainable by PA0 (I) foaming a polymerizable aqueous mixture which comprises PA1 (a) monoethylenically unsaturated monomers which contain acidic groups and are at least 50 mol % neutralized, PA1 (b) with or without other monoethylenically unsaturated monomers, PA1 (c) crosslinkers, PA1 (d) initiators, PA1 (e) 0.1-20% by weight of at least one surfactant, PA1 (f) with or without at least one solubilizer and PA1 (g) with or without thickeners, foam stabilizers, polymerization regulators, fillers and/or cell nucleating agents, where the foaming takes place by dispersing fine bubbles of a gas which is inert to free radicals, and PA0 (II) polymerizing the foamed mixture to form an expanded hydrogel and adjusting the water content of the expanded polymer to 1-45% by weight, a process for their production and their use in hygiene articles employed to absorb body fluids and in dressing material for covering wounds.