Expanded polystyrene (EPS), a foaming agent is added to the polystyrene, so that when heated, the blowing agent softens and generates a gas, making the polystyrene a rigid closed cell foam. The uniform and closed cavity structure makes the EPS have the characteristics of small water absorption, excellent dielectric properties, light weight and high mechanical strength. With sound absorption, sound insulation, heat insulation and other effects. Further, in order to increase the safety of its use, a halogenated hydrocarbon is added as a flame retardant to the material to form a flame retardant expanded polystyrene.
