This research investigates the effect of calcium carbonate nano particles on morphology, mechanical properties and crystallization behavior of Polypropylene/Poly (ethylene terephthalate) (PP/PET) blend. Accordingly, the various samples containing 3, 5 and 8 phr of calcium carbonate nano particles were prepared via melt-mixing. The outcomes of SEM micrographs showed that the specimen containing 3 phr of nano calcium carbonate along with 5%wt of PP-GMA influences in morphology development of PP/PET far from the other samples. Additionally, the sample filled by 3 phr of nano particles illustrated the highest level of young modulus and tensile strength compared to other specimens. According to crystallization studies, the crystallinity of PP increased about 13% and the crystallinity of PET decreased about 8% with compatibilization of PP/PET blend. Moreover, with addition of nano calcium carbonate to compatibilized PP/PET blend, the crystallinity of PP decreased near 14% and the crystallinity of PET increased about 42%. The approximation of crystallization behavior with Avrami model showed that with compatibilization of PP/PET and adding of nano calcium carbonate to compaibilized PP/PET blend, the crystallization rate of PET phase decreased. The crystallization rate of PP phase did not change so much with compatibilization and addition of calcium carbonate nano particles. The estimation of experimental data with Ozawa model indicated that the addition of compatibilizer to PP/PET blend has led to increase the crystal growth dimension (m) of PP and decrease the crystal growth rate (K) of PP. With adding 3 phr of calcium carbonate nano particles to compatilibilized PP/PET blend, m and K values of PET phase decreased about 18% and 56%, respectively. Moreover, m and K values of PP phase reduced about 18% and 3%, respectively. Keywords: Calcium carbonate nano particles, PET, PP, Morphology, Crystallization
