Blends of natural rubber/virgin ethylene-propylene-diene-monomer (NR/EPDM) and
natural rubber/recycled ethylene-propylene-diene-monomer (NR/R-EPDM) were
prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the
blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding,
mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM
blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and
NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for
increasing weight ratio of EPDM or R-EPDM.