Fig. 2 shows the relationship between stress and strain of the tensile test of the OE-MNR/HDPE TPVs. It is clear that all TPVs show similar values of the initial slope at the beginning of the curves. This reflects the similar value of an initial modulus and, hence, stiffness of the material. In consideration of the area under the curve for toughness, the blend without the comaptibilizer shows the lowest stress value. The TPVs with the compatibilizers showed higher values and the order of the toughness can be ranked as follows: TPV with PhHRJ-PE >TPV with PhSP-PE>TPV with HDPE-g-MA. Mechanical properties in terms of tensile strength and elongation at break of the stress–strain curves in Fig. 2 are summarized in Table 4.