Ammonium polyphosphate (APP) is an inorganic compound widely used in flame retardants and fire extinguishers. Its chemical formula is (NH4PO3)n, where n represents the degree of polymerization. The application of APP in fire extinguishers is mainly based on its excellent flame retardant and smoke suppression properties.
First, the main role of APP in fire extinguishers is as a flame retardant. It inhibits the spread of flames and the combustion process through a variety of mechanisms. APP decomposes at high temperatures to produce phosphoric acid and ammonia. Phosphoric acid forms a glassy protective film on the combustion surface, isolating oxygen and heat, thereby preventing the continuation of combustion. Ammonia helps dilute the combustible gas in the combustion area and reduce the temperature of the flame.
Secondly, APP has good smoke suppression properties. In a fire, smoke not only reduces visibility and increases the difficulty of escape, but also contains a large amount of toxic gases, posing a serious threat to human health. APP can effectively reduce the generation of smoke during the combustion process and reduce the harmfulness of the fire.
Ammonium polyphosphate is used in fire extinguishers in various forms, the most common of which are dry powder fire extinguishers and foam fire extinguishers. In dry powder fire extinguishers, ammonium polyphosphate is one of the main ingredients and is mixed with other chemicals to form an efficient fire extinguishing dry powder. This dry powder can quickly cover the burning material, isolate oxygen, and quickly extinguish the flame. In foam fire extinguishers, ammonium polyphosphate is mixed with a foaming agent to form a stable foam that covers the surface of the burning material, playing a role in cooling and isolating oxygen.
In addition, ammonium polyphosphate also has the advantages of environmental protection and low toxicity. Compared with traditional halogenated flame retardants, ammonium polyphosphate does not release harmful halides during combustion, reducing the harm to the environment and human body. Therefore, the application of ammonium polyphosphate in modern fire extinguishers has received more and more attention.
In general, the application of ammonium polyphosphate in fire extinguishers has multiple advantages, including efficient flame retardant performance, good smoke suppression effect, and environmental protection and low toxicity. With the advancement of science and technology and the improvement of people’s requirements for safety and environmental protection, the application prospects of ammonium polyphosphate in fire extinguishers will be broader.
Post time: Sep-20-2024
