Electroviscous liquids

US4645614A · kind A · utility

Assignees

• BAYER HEALTHCARE LLC · DE
• Metzeler Kautschuk GmbH · DE

Inventors

• John Goossens · Cologne, DE
• Gunter Oppermann · Dietzenbach, DE
• Wolfgang Grape · Cologne, DE
• Volker Hartel · Germering, DE

Key dates

• Filing date: Jul 9, 1985
• Grant date: Feb 24, 1987
• Expiry date: Jul 9, 2005

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S516/07
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The electroviscous suspension is based on a mixture of aqueous silica gel with silicone oil as the liquid phase to which a dispersant is added. The dispersant consists of amino functional or silicon-functional polysiloxanes having a molecular weight above 800. The concentration of the dispersant is from 1 to 30% by weight and preferably from 5 to 20% by weight, based on the silica gel particles. Electroviscous suspensions such as these are distinguished by the fact that they are highly compatible with elastomeric materials, non-sedimenting, non-inflammable and physiologically acceptable. In addition, they are heat- and freeze-resistant over a wide temperature range and are largely unaffected by temperature and pressure in their viscosity.