Polypropylene (PP) nanocomposite is prepared by reactive processing method to improve the thermo-mechanical properties of virgin PP. PP nanocomposite exhibits pronounced improvement in crystallization temperature (Tc), heat distortion temperature and tensile properties when compared with virgin PP. The melting and crystallization behaviours of the neat PP and the nanocomposite are studied by conventional and modulated differential scanning calorimetry and optical microscopy. The non-isothermal crystallization kinetics is studied using different models, c.a. Ozawa, Avrami and combined Avrami-Ozawa models. Results indicate that half time of crystallization at a particular cooling rate remains unchanged in neat PP and the nanocomposite. However, super cooling effect is pronounced in the nanocomposite when compared with neat PP. Irrespective of cooling rate there is approximately 14% improvement in Tc in PP nanocomposite with respect the neat PP. Such an improvement in Tc with improved thermo-mechanical properties are highly desirable for rigid packaging applications.