Crystallization and melting behavior of PP/CaCO3 nanocomposites during thermo-oxidative degradation

The crystallization and melting behavior of PP/CaCO3 nanocomposites during thermo-oxidative degradation process were studied using differential scanning calorimetry and X-ray diffraction. The results indicated that addition of nano-CaCO3 and compatibilizer significantly reduced the thermo-oxidative stability of PP. Before degradation, thermal aging resulted in an increase in the melting temperature and crystallinity of PP due to the annealing crystallization. Thermo-oxidative degradation decreased the melting temperature and increased melting range, and caused an increase in crystallinity of PP due to the chemi-crystallization. The investigation also indicated that the influence of degradation on the small crystals were much more significant than that on the large ones.