Abstract:  The sound insulation behaviors of the inorganic particle-filled polymer composites were analyzed by means of the acoustics theory with the purpose of revealing the sound insulation mechanisms of the composites．Based on the analysis, a relevant mathematical model was then established, and the sound insulation properties of the glass beadfilled polyethylene composite were finally predicted．The results indicate that there is a linear relationship between the capacity of sound insulation and the volume fraction of glass beads, and the capacity is significantly sensitive to the sound frequency．It is also indicated that with a constant volume fraction of glass beads, the capacity of sound insulation decreases with the increase of the bead size．The principal cause for the improvement of sound insulation property lies in the behaviors of reflection, scattering and refraction which occur under the condition of sound wave contacting the particles．

Key words: polymer, inorganic particle, composite, sound insulation property, theoretical model