Studies on Crystallization and Melting Behaviors of UHMWPE/ MWNTs Nanocomposites with Reduced Chain Entanglements

The nonisothermal crystallization and melting behavior of UHMWPE (ultra-high molecular weight polyethylene)/ MWNTs (multi-walled carbon nanotubes) nanocomposites with reduced chain entanglements was studied using differential scanning calorimetry (DSC) technique. The Ozawa approach failed to describe the crystallization behavior of nanocomposites, whereas the modified Avrami analysis could explain the behavior of UHMWPE/ MWNTs nanocomposite to some extent. A novel kinetic model by Liu et al. was able to satisfactorily describe the crystallization behavior of UHMWPE/MWNTs nanocomposites. The Dobreva and Kissinger methods failed to calculate the nucleation activity and activation energy, respectively, for the UHMWPE/MWNTs systems. Also the Vyazovkin model-free kinetic method was applied to nonisothermal crystallization to evaluate the dependence of the effective activation energy on conversion and temperature.