Fumed silica, trichlorosilane

The chemistry of silicone halides was recently reviewed by Collins.13 The primary use for SiCU is in the manufacturing of fumed silica, but it is also used in the manufacture of polycrystalline silicon for the semiconductor industry. It is also commonly used in the synthesis of silicate esters. T richlorosilane (another important product of the reaction of silicon or silicon alloys with chlorine) is primarily used in the manufacture of semiconductor-grade silicon, and in the synthesis of organotrichlorosilane by the hydrosilylation reactions. The silicon halohydrides are particularly useful intermediate chemicals because of their ability to add to alkenes, allowing the production of a broad range of alkyl- and functional alkyltrihalosilanes. These alkylsilanes have important commercial value as monomers, and are also used in the production of silicon fluids and resins. On the other hand, trichlorosilane is a basic precursor to the synthesis of functional silsesquioxanes and other highly branched siloxane structures. 

The physical properties of cured polysiloxane materials are dramatically influenced by fillers (1,2). So-called non-reinforcing (extenders) and reinforcing fillers are typically used the most common reinforcing filler is silica. High surface area silica, called fumed silica, is formed by burning the product mixture obtained from the trichlorosilane (TCS) reaction of equation 8. Only a small amount of untreated... 

Silicon is used to make trichlorosilane to produce silicon tetrachloride, which is used as a feedstock to produce fumed silica, commonly used with silicone rubber as a reinforcing filler. 

Trichlorosilane is used to make silicon tetrachloride, which is used to make fumed silica that is mainly used as the filler in silicone rubber compounds. 

Trichlorosilane is mostly used in producing fumed silica. Many of the applications for fumed silica are nonrubber. 

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