Nanosized Sb2O3 flame retardant was prepared by homogeneous precipitat ion in ultrasonic field. The preparation conditions were studied and optimized. Nanosized Sb2O3 was characterized by means of powder X-ray diffraction (XRD), tr ansmission electron microscopy (TEM) and the specific surface area. XRD, TEM res ults indicate that the crystalline form of nanosized Sb2O3 is face-centered cubi c with an average size of 15 nm. The application of ultrasonic wave is to decrea se the particle size of nano-Sb2O3 and to improve its dispersivity. The mechanic al properties and flame retardancy of the flame retarding polyethylene(PE) foams were much improved with the application of nano-Sb2O3.
