MECHANICAL PROPERTIES AND MORPHOLOGY OF POLYPROPYLENE/POLYETHYLENE BLENDS.

Isotactic polypropylene (PP) was blended with high or low-density polyethylene (HDPE) or LDPE) through extrusion to investigate the variation of tensile strength, heat deflection temperature, and impact strength with the composition of the material. The microstructures of polyblends have been studied to interpret the apparent mechanical behavior through a number of techniques, such as dynamic viscoelasticity, differential scanning calorimetry, picnometry and scanning electron microscopy. It has been found that the impact strength of PP was improved by adding PE, especially LDPE, but the tensile strength and heat deflection temperature mostly decreased with increasing PE content.