Morphology and Crystallisation Kinetics of Polyethylene / Montmorillonite Nanocomposites

The crystallisation kinetics of blend systems containing 10:90 parts high density to low density polyethylene were studied using differential scanning calorimetry (DSC.) Single-screw extrusion was used to prepare the blends, with and without masterbatch but with identical shear histories. Two masterbatch systems were purchased from separate suppliers and with different organomodifiers: octadecylammonium (Nanocor C30PE) and dimethyl-di (hydrogenated tallow) quaternary ammonium (Nanoblend 2101.) The samples were prepared with and without maleic anhydride grafting on the high density component. Avrami analysis was used to analyse the crystallisation kinetics of the high density component in the low density melt, thereby elucidating the influence of the modified clay. SEM micrographs demonstrate that the Nanocor systems have enhanced nucleation and highly disordered morphologies. By contrast, there appears to be only subtle disordering effect in the Nanoblend systems, without any significant change in crystallisation kinetics.