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The so-called flame retardant is an additive that can improve the flame retardancy, self-extinguishing or smoke suppression of flammable or combustible materials. It is one of the main additives for important fine chemical products and synthetic materials. Flame retardants are developing with the development of synthetic materials. As the voice of flame retardant and disaster prevention is rising all over the world and the laws and regulations of flame retardant are improving, the research, development and production of flame retardant chemicals are promoted directly.



Since the 1960s, the world flame retardant market has undergone a vigorous development stage. At present, there are hundreds of different kinds of flame retardants, and new types of flame retardants still emerge in endlessly. According to the flame retardant processing methods of materials, flame retardants can be divided into two categories: additive type and reactive type. Additive flame retardants are mostly used in plastics, while reactive flame retardants are mainly used in thermosetting resins such as epoxy resins and polyurethane resins. Its common characteristics are that it does not reduce the physical properties of polymer materials, such as heat resistance, mechanical strength and electrical properties, does not decompose at processing temperature, has low toxicity and good weather resistance. According to the flame retardant elements, it can be roughly divided into scale flame retardant, halogen flame retardant, aluminium flame retardant, magnesium flame retardant, silicon flame retardant and so on.



Flame retardants are closely related to combustion. According to the viewpoint of ****, combustion reaction has four elements: fuel heat source, oxygen and chain reaction. Generally, the combustion of polymers can be divided into three stages: pyrolysis, thermal ignition (spontaneous combustion) and hot spot combustion (combustion propagation). By using the corresponding flame retardants to resist the four elements of combustion in different combustion stages, various flame retardant mechanisms have been formed, including condensed phase flame retardant mechanism, gas phase flame retardant mechanism and interruption of heat exchange mechanism.



With people's attention to the flame retardant of flammable materials, flame retardants have been greatly developed with the extensive application of polymer materials. With the enhancement of people's awareness of environmental protection, new flame retardant varieties are constantly emerging, and some new technologies are also constantly applied to the research and production of flame retardants.