Environmental protection flame retardant in the fire to play three major roles:
1. Cover effect In the combustible material by adding environmentally friendly flame retardant, at high temperatures can be formed in a glass or stable foam cover, isolated oxygen, with insulation, oxygen, to prevent the escape of combustible gas out to achieve Flame retardant purpose. The reason is that on the one hand can prevent further pyrolysis of the polymer, on the other hand to prevent the internal thermal decomposition of the product into the gas phase involved in the combustion process.
2. Inhibition of chain reaction According to the theory of combustion chain reaction, to maintain the combustion is required free radicals. The environmentally friendly flame retardant can act on the gas phase combustion zone, prevent the flame from spreading, so that the flame density of the combustion zone is reduced and the combustion reaction rate is reduced until it is terminated. Such as halogen-containing flame retardants, the evaporation temperature and polymer decomposition temperature is the same or similar, when the polymer heat decomposition, the flame retardant also volatile, it can capture the combustion reaction of free radicals, thus preventing the flame propagation , The flame density of the combustion zone is reduced, and the combustion reaction rate is finally reduced until it is terminated.
3. Non-combustible gas asphyxiation When the environmentally friendly flame retardant is decomposed when it is heated, it is not conducive to the combustion gas, and the flammable gas concentration is diluted below the combustion lower limit, dilute the oxygen concentration in the combustion zone, prevent the combustion from proceeding, effect.