Morphology and mechanical properties of immiscible polyethylene/polyamide12 blends prepared by high shear processing

In this work, completely immiscible polyethylene/polyamide12 (PE/PA12) blends were prepared by high shear extruder. The morphology and mechanical properties of the blends were investigated as a function of rotation speed. It was found that the high shear processing is an effective method to improve the dispersion of the PA12 phase in PE matrix when PA12 contents are 5 wt% and 10 wt%, and the dispersed phase particle size is reduced with the increase of rotation speed from 100 r/min to 500 r/min. However, with further increase of PA12 content to 20 wt%, high shear processing has no effect on the phase morphology of the blends. Accordingly, a largely increased elongation at break and impact strength are observed for PE/PA12/95/5 and PE/PA12/90/10 blends obtained at high rotation speeds but no effect on the property of PE/PA12/80/20. Annealing experiment demonstrated that the obtained phase morphology is not stable thus compatibilizer should be introduced in the future work. This work could provide a guideline for the application of high shear processing in the preparation of polymer blends with huge polarity difference.