Volatile metal halide species formation

From a mechanistic perspective, one of the most important aspects of the results of these experiments is the further confirmation of the formation of volatile metal halide species by a reaction pathway, as illustrated by Scheme [6], that does not include the formation of HX. 

The tin additives exert their fire-retardant action in both the condensed and vapour phases, by promoting the formation of a thermally stable carbonaceous char and (in halogen-containing polymer formulations) by generating volatile metal halide species which assist in free radical scavenging reactions in the flame. 

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