Effect of blend ratio on cure characteristics, tensile properties, thermal and swelling properties of mica-filled (ethylene-propylene-diene monomer)/(recycled ethylene-propylene-diene monomer) (EPDM/r-EPDM) blends

(Ethylene-propylene-diene monomer)/(recycled ethylene-propylene-diene monomer) (EPDM/r-EPDM) blends filled with constant mica loading were compounded at various blends ratios (i.e., 90/10, 80/20, 70/30, 60/40, and 50/50). Results indicated that scorch time decreased with increasing r-EPDM content, whereas curing time, minimum torque, and maximum torque show the opposite trend. The tensile strength, stress at 100% elongation, and elongation at break value increased with increasing r-EPDM loading in the blend systems and the optimum properties occurred at 70/30 EPDM/r-EPDM blends ratio. The thermal stability of EPDM/r-EPDM blends increased with increasing r-EPDM content in the blends but the swelling percentage showed the opposite trend with a greater addition of r-EPDM content in the blends. J. VINYL ADDIT. TECHNOL., 21:1–6, 2015. © 2014 Society of Plastics Engineers