Effect of compatibilizer and clay on morphology and fracture resistance of immiscible high density polyethylene/polyamide 6 blend

In this work, compatibilizer (maleic anhydride grafted high density polyethylene, HDPE-g-MA) and clay were introduced into immiscible HDPE/polyamide 6 (PA6) blend. Three different blending sequences were selected to prepare the nanocomposites. The distribution states of clay in different nanocomposites were characterized using wide angle X-ray diffraction (WAXD) and transmission electron microscope (TEM). The cooling and melting behaviors of HDPE matrix and PA6 particles were investigated by using differential scanning calorimetry (DSC). Scanning electron microscope (SEM) was used to characterize the morphology of nanocomposites. The results showed that clay in all the nanocomposites had a tendency to selectively distribute in PA6 particles and formed the exfoliated structure. Specifically, there was a synergistic effect of HDPE-g-MA and clay in decreasing the PA6 particles and improving the particles size distribution, and the degree of the synergistic compatibilizing effect was dependent on the blending sequence of the nanocomposites. As a consequence, the fracture resistance including the elongation at break (%) and notched Izod impact strength could be enhanced in different degrees. Further researches based on the application of different contents of clay were carried out and the results show that the content of clay also influenced the microstructure and mechanical properties of the nanocomposites.