Flame retardant, as the name suggests, is a kind of preparation that can effectively prevent fire, making flammable materials become flame-retardant or even non combustible after being treated or added. It is a functional auxiliary that gives the flammability of flammable polymers, which is mainly designed for the flame retardancy of polymer materials. There are many types of flame retardants, which can be divided into additive flame retardants and reactive flame retardants according to the use methods.