Preparation of Ziegler-Natta Catalysts for the Synthesis of Polypropylene/Carbon Nanotubes Nanocomposites by in situ Polymerization

Abstract

Aiming to improve the dispersion of carbon nanotubes (CNT) in a polymer matrix, a fourth-generation Ziegler-Natta, ZN, catalyst was prepared in the presence of CNT to synthesize nanocomposites of polypropylene (PP/CNT) by in situ polymerization. The performance of the ZN catalyst was evaluated along with the thermal (TGA and DSC) and dynamic-mechanical properties of the nanocomposites and they were compared with those of neat PP synthesized with the standard catalyst prepared without carbon nanoparticles. The thermal degradation temperature of the PP/CNT nanocomposite increased in comparison with that of neat PP. Moreover, the crystallization temperature and the degree of crystallinity sharply increased in PP/CNT materials. Finally, the storage modulus of the nanocomposite prepared by 30 min of polymerization increased, as well as the Tg.