Using Devulcanized EPDM in PP/HDPE/EPDM Ternary Blend: Mechanical Properties and Morphology

Due to rapid increase in consumption rate of EPDM in rubber industry in the last decade, recycling and reusing of this rubber have attractive and extensive studies. lending with the other polymers can be an efficient method for reusing of ecycled EPDM. In this study, ternary blends of polypropylene (PP), high density polyethylene HDPE) and mechano-chemical devulcanized EPDM (D-EPDM) were prepared sing a laboratory twin-screw extruder. Three levels of D-EPDM (20, 40, 60 t%) at constant concentration of HDPE (20 wt%) were used. Sulphur dynamic vulcanization as applied on the samples. Mechanical properties such as: tensile properties, ompression set, hardness, impact resistance and morphology of samples ere studied and compared to samples containing virgin EPDM. Tensile strength and ompression set decreased with increase in both D-EPDM and EPDM content in the ernary blend. Dynamic vulcanization improved the mechanical properties and its ffect on the samples containing D-EPDM was more considerable. The dominant morphology f both ternary blends was the separate dispersion of HDPE and EPDM (or -EPDM) in the PP matrix. The D-EPDM formed droplets dispersed in PP matrix similar o the virgin EPDM.