... purity 4.Surface chemical 5.hydrophobic Sealed fumed silica Sealed fumed silica has size small, super specific surface area, ... , thickening sex, thixotropy, electrical insulation, etc. Sealed fumed silica is mainly used for Silicone Rubber ,Adhesives, Sealants,Coatings, ... Paints and Inks,Rubber ,plastic,etc. Sealed fumed silica is a synthetic,amorphous,colloidal silicon dioxide that is ...