Abstract: The polybutylene (PB) foam was prepared by compression molding， and the effect of the content and particle size of nucleating agents on the mechanical properties and cellular structure of foam was studied. When talc and calcium carbonate were used as nucleating agent, the average cell diameter was reduced to 135 μm, and the cell density was increased to 7×105 cells/cm3. The smaller particle size the nucleating agent, the greater the cell density, and the smaller the average cell diameter. When calcium carbonate was used as a nucleating agent with loading of 6 %, a foam with particle size of 10 μm, cell density up to 106 cells/cm3, and average cell diameter size of 85 μm was obtained.

Key words: polybutylene, nucleation mechanism, cellular structure, mechanical property