Hydrophilic silica for sealants

US8617504B2 · kind B2 · utility

Assignee

• EVONIK DEGUSSA GMBH · DE

Inventors

• Christian Panz · Wesseling, DE
• Helga Obladen · Zeven, DE
• Rene Allerdisse · Bornheim, DE
• Karl Meier · Bornheim, DE
• Markus Ruf · Meckenheim, DE
• Michael Kempf · Rodenbach, DE
• Mario Scholz · Zöblitz, DE
• Dieter Kuhn · Marburg, DE

Key dates

• Filing date: May 29, 2007
• Grant date: Dec 31, 2013
• Expiry date: Sep 15, 2031

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01B33/193
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Hydrophilic precipitated silicas which combine a particularly low initial moisture content with low moisture absorption over time, a low tapped density and a low silanol group density, have the following physicochemical parameters: equilibrium moisture content (at 70% relative humidity/20° C.) of 0.5%-5.0% by weight, based on the weight of the hydrophilic precipitated silica, BET surface area of 50-250 m2/g, CTAB surface area of 50-250 m2/g, and DBP (anhydrous) of 200-350 g/100 g.