Synergistic effects of toughening of nano-CaCO3 and toughness of β-polypropylene

High performance β-polypropylene (β-PP) nanocomposites were prepared by nano-CaCO3 with β-nucleation (β-CC) filled PP, and the crystallization and mechanical properties of β-PP nanocomposites were investigated. The results show that β-CC prepared by nano-CaCO3 supported β-nucleating agent calcium pimelate (CaPA) does not only increase the crystallization temperature of PP, but also induce the forming of a number of β-PP. It indicates that the nucleation mechanism of nano-CaCO3 has been changed from α- to β-nucleation. The notched impact strength of β-CC filled PP nanocomposites was higher than that of CC filled PP and CaPA nucleated PP. It is suggested that there is a synergistic effect of toughening of CC and toughness of β-PP. Meanwhile, the reinforcing of CC nanoparticles increased the stiffness of β-PP. The synergistic toughening effect of CC and β-PP was discussed. This method can be extended to prepare other high performance filled β-PP composites.