Melt-crystallization behavior and non-isothermal crystallization kinetics of UHMWPE/HDPE/MWCNTs nanocomposite

The melt-crystallization behavior and nonisothermal crystallization kinetics of ultra high molecular weight polyethylene and high-density polyethylene (UHMWPE/HDPE) blends and their nanocomposites with 1 wt% of multi-wall carbon nanotubes (MWCNTs) were examined in this study. Blends of UHMWPE and HDPE and their nanocomposites with MWCNTs, were prepared by melt mixing in an internal mixer, in the entire range of blending ratio. Crystallization behavior and nonisothermal crystallization kinetics were investigated by differential scanning calorimetry (DSC). The blends and their nanocomposites showed the single-peak in both crystallization exotherms and melting endotherms. It was concluded that components in blends crystallize individually when cooled from the melt. The crystallite of UHMWPE act as the nucleating agent for HDPE. Based on the results, MWCNTs in the 20wt% of UHMWPE in nanocomposites accelerated the crystallization and acted as nucleating agent but in higher contents of UHMWPE, the nanocomposite crystallization was slightly delayed and the MWCNTs did not act as nucleating agents. Analysis of the nonisothermal crystallization data was carried out based on the Ozawa model. Kinetics studies have revealed that crystallization of blends proceeds via heterogeneous nucleation and is governed by one-dimensional growth