Flame retardant, as its name implies, is a preparation that can effectively hinder fire, making flammable materials difficult to burn or even incombustible after being treated or added. It is a functional additive that endows flammable polymers with flame retardancy, and is mainly designed for 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 their use methods.