Inhibition chain reaction of flame retardants

According to the chain reaction theory of combustion, what is needed to sustain combustion are free radicals. Flame retardants can act on the gas phase combustion zone to capture free radicals in the combustion reaction, thereby preventing the propagation of the flame, reducing the flame density in the combustion zone, and finally reducing the combustion reaction speed until it is terminated. Such as halogen-containing flame retardants, its evaporation temperature and polymer decomposition temperature is the same or similar, when the polymer is decomposed by heat, the flame retardant is also volatilized at the same time. At this time, the halogen-containing flame retardant and the thermal decomposition product are in the gas phase combustion zone at the same time, and the halogen can capture the free radicals in the combustion reaction and interfere with the combustion chain reaction.