Tetrabromobisphenol A Bis(2,3-dibromo-2-methylpropyl ether)/XZ68T Suitable for the flame retardancy of XPS, EPS and PP. No antimony trioxide is required when used for flame-retardant XPS or EPS; it has high flame retardant efficiency and can impart a B1 flame retardant rating to foam materials. Its flame retardant efficiency in PP is higher than that of octabromoether, and it can endow PP materials with UL-94-V0 flame retardant rating while retaining the mechanical properties of PP materials to the maximum.