SiSiB® FS-0100 Fumed Silica is a hydrophilic fumed silica with a specific surface area of 100 m2/g. Hydrophilic fumed silica is manufactured by hydrolysing volatile chlorosilanes in an oxyhydrogen flame. In chemical terms, the loose white powder consists of highly pure amorphous silicon dioxide. Hydrophilic silica is wetted by water and can be dispersed in water. Hydrophobic silica is produced by the chemical reaction of hydrophilic silica with reactive silanes, e.g. chlorosilanes or hexamethyldisilazane. It has water-repellent properties and is no longer dispersible in water.