Shanghai flame retardant textile combustion mechanism (as a feedback mechanism) process, in which the fuel (from thermal degradation or pyrolysis fibers), heat (from ignition and combustion) and oxygen (from air) are all Works as the main ingredient. To interrupt this mechanism, five methods (a) to (e) have been proposed. Flame retardants can work in one or more of these ways. The following are the stages and related flame retardant effects: a) heat removal; b) increase the decomposition temperature; c) reduce the formation of combustible volatiles and increase the amount of carbon; d) reduce contact with oxygen or dilute the flame; e) Interfering with flame chemical reactions and / or increasing fuel ignition temperature (Tc); melting and / or degrading and / or dehydrating require large amounts of heat to be absorbed (for example, preparations containing inorganic and organic phosphorus in the back coating, aluminum hydroxide or water Into alumina). It is generally not used by flame retardants; it is more common in inherently refractory and heat resistant fibers such as aramid fibers. Most phosphorus and nitrogen-containing flame retardants in cellulose and wool; heavy metal complexes in wool. Hydrated and certain carbon-promoting flame retardants can release water; halogen-containing flame retardants can release hydrogen halides. Halogen-containing flame retardant, often combined with antimony oxide. From the above, it can be seen that certain types of flame retardants can function in multiple ways, and most effective examples are the case. In addition, certain flame retardant formulations can produce liquid-phase intermediates that wet the surface of the fiber and thus act as a barrier to heat and oxygen-a well-accepted borate-boric acid mixture works in this way Play a role. In addition, it promotes char formation. To simplify the classification of the different ways of chemical flame retardant behavior, the terms 'condensate' phase and 'gas or vapor' phase activity can be used to distinguish them. Both are composite terms, the former including the above (a ~ c) methods, and the latter including (d) and (e) methods. Physical mechanisms usually work at the same time. These mechanisms include the formation of a coating to remove oxygen and / or heat (mode d), increase the heat capacity (mode a), and dilute or cover the flame with non-flammable gases (mode d).