Xerogels and process for their preparation

US5795556A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Rolf Jansen · Braunschweig, DE
• Andreas Zimmermann · Griesheim, DE
• Eric Jacquinot · Compiègne, FR
• Douglas M. Smith · Albuquerque, US

Key dates

• Filing date: Jun 20, 1996
• Grant date: Aug 18, 1998
• Expiry date: Jun 20, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01B33/16
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Xerogels and a process for their preparation involving acidifying an aqueous waterglass solution, polycondensing the resulting silica by addition of a base, removing most of the water from the gel by washing the gel with an organic solvent, reacting the resulting gel with a silylation agent and then drying the silylated gel under subcritical conditions.