The mechanical properties of the NR/PP TPVs cured with the various types and concentrations of peroxide are given in Fig. 4, Fig. 5, Fig. 6 and Fig. 7. In Fig. 4, there is a clear trend of increasing tensile strength when the concentration of crosslinking agents increases. The TPVs prepared using DCP or DTBPIB as curatives provide superior tensile strength relative to the blends crosslinked with DTBPH or DTBPHY at all concentration levels. The TPV with 10 meqs of DTBPIB shows overall the highest tensile strength.