White carbon black is a general term for white powder X- ray amorphous silica and silicate products. The first is silica gel, fumed silica and fine silica gel, and also consists of powdered aluminum silicate and calcium silicate. Silica is a porous material, and its composition can be shown by SiO2 · nH2O, which exists in the form of surface hydroxyl. Soluble in caustic soda and hydrofluoric acid, insoluble in water, solvent and acid (hydrofluoric acid outside). High temperature resistant, nonflammable, tasteless, odorless, with good electrical insulation. There are three kinds: isolated hydroxyl, ortho hydroxyl and two-layer hydroxyl. The relationship between different hydroxyl content and production process is as follows: the surface hydroxyl of newly produced fumed silica is mainly isolated hydroxyl. With the extension of time and the addition of water adsorbed on the surface, the surface siloxy of fumed silica can be transformed into silicon hydroxyl (once silicon hydroxyl is formed, it will form Ortho hydroxyl with ortho hydroxyl which is originally isolated), so the number of isolated hydroxyl will be reduced, The ortho hydroxyl group will be added.

　　A silane coupling agent named tetramethyldivinyldisilazane is needed to modify the fumed silica. It is a colorless transparent liquid and soluble in most organic solvents such as ethyl acetate, toluene and cyclohexane. CAS No.: 7691-02-3, mainly used for surface treatment of fumed silica in liquid silicone rubber products. The treated silica with normal addition of 2% - 5% changes from hydrophilic to hydrophobic and can be compatible with raw rubber.

　　Tetramethyldivinyldisilazane also has other uses, which can be used as an intermediate of chemicals such as hospitals; It can be used as coating additive; It can be used in the manufacture of silicone rubber, silicone colloid and vinyl silicone resin; It can be used as ceramic surface treatment agent.

　　Precautions: during storage, do not touch open fire. Keep it ventilated and dry to prevent sunlight. The storage temperature is - 45-40; During transportation, collision, rain and sun shall be prevented; Store and transport as dangerous goods.

　　Source: semiconductor chemical manufacturer   www.sun-chem.cn