Hydrophilic silica for sealants
AssigneeEvonik Degussa GmbH
InventorsChristian Panz, Helga Obladen, Rene Allerdisse, Karl Meier, Markus Ruf, Michael Kempf, Mario Scholz, Dieter Kuhn
Life of this patent
Estimating the term…
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.
Claims23
A hydrophilic precipitated silica, having the following physicochemical parameters:
- Equilibrium moisture content
- 0.5%-5.0% by weight, based on the
- (at 70% relative humidity/20° C.)
- weight of the hydrophilic
- precipitated silica;
- BET surface area
- 50-250
- m2/g;
- CTAB surface area
- 50-250
- m2/g;
- and
- DBP (anhydrous)
- 200-350
- g/100 g,
- wherein the silica has a pH of 4-6.5.
Dependencies are inferred from the claim text.