Crystallization and melting behavior of PP/nano-CaCO3 composites with different interfacial interaction

The effect of different interfacial interaction on the crystallization and melting behavior of PP/nano-CaCO3 composites was investigated using differential scanning calorimetry, X-ray diffraction and polarized optical microscope. The results indicated that nano-CaCO3 acted as heterogeneous nuclei for PP crystallization. There existed a synergistic effect of heterogeneous nucleation between nano-CaCO3 and compatibilizer for PP crystallization, which was proved by increasing the crystallization rate and decreasing the fold surface free energy as well as favoring the formation of beta-crystal of PP. However, this synergistic effect was dependent on the interfacial interaction between PP and compatibilizer. The increased miscibility between compatibilizer and PP favored this synergistic effect.