Silicon halides elemental halogens

Work in Russia has shown that the use of elemental silicon plus tin chloride can enhance the flame retardancy of both polypropylene and polyamide 66 compounds. Silicon tetrahalides are formed in the gas phase of combustion and inhibit the chain reactions that develop in a fire. These silicon halides do not act like halogen hydrocarbons in the atmosphere so there is no likelihood of contributing to ozone depletion. 

Halide transfer to other elements has also been observed. In particular, in view of the strength of the silicon-halogen bond, it is not surprising that silyl ions, H3Si+, readily undergo CT transfer from the chloromethanes CH Cl (x = 0-3) and F" transfer from CF4 and CHF38. 

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