Non-isothermal crystallization kinetics of polyethylene/carbon nanofiber composites

Abstract

The effect of carbon nanofibers on the crystallization of polyethylene using differential scanning calorimetry operating in dynamical mode at various cooling rates (2, 4, 8, 15, and 30°C/min) is reported. Experimental data were analyzed using the Avrami, Ozawa, and the combined Avrami–Ozawa methods. It is concluded that the addition of carbon nanofibers modifies the crystallization process of polyethylene (changing the value of the Avrami exponent), and that the combined Avrami–Ozawa approach describes more accurately the crystallization of carbon nanofiber reinforced polyethylene composites. The analysis of the experimental data indicates that the dispersion of carbon nanofibers within polyethylene leads to complex changes in the crystallization process such as increased crystallization temperature, longer times to reach 50% crystallization, higher crystallization rates, and lower degrees of crystallinity of the polymeric component.