Enhancement of Processability of EPDM /Pistachio Shell Biocomposites by Ethylene‐Octene Random Copolymer: Study of Mechanical, Rheological, Dynamic Mechanical, Thermal, and Morphological Properties

ABSTRACT

EPDM (ethylene propylene diene terpolymer), being a non‐biodegradable polymer, is becoming an environmental issue after post‐use discard. Thus, to incorporate a biodegradable component into it, EPDM/pistachio shell (PS) biocomposites are prepared. Composite formation is successful up to 40 wt% of filler incorporation, beyond which processability is hampered and composite preparation is not possible. Therefore, EPDM has been blended with ethylene‐octene copolymer (Polyolefin Elastomer, POE) prior to composite preparation. EPDM/POE blend (80 wt%/20 wt%) is found to be able to hold up to 60 wt% PS, forming biocomposites with improved properties. The composites show improved processability owing to the distinctive processing behavior of POE, demonstrated by rheological analysis. The observation of complex viscosity and crossover frequency reveals that POE plays a significant role in enhancing the processability of blend‐based biocomposites. The filler‐containing capability of EPDM is enhanced from 40 to 60 wt% in the presence of POE. Further, for EPDM/POE/PS (60 wt% PS) biocomposite, Young's modulus is increased by 420% compared to the EPDM/POE blend, and around 1000% compared to EPDM. DMA investigations indicate approximately 105 MPa and 13 MPa enhancement in storage modulus and loss modulus of the EPDM/POE/PS (60 wt% PS) biocomposites compared to those of the EPDM/POE blend at 30°C, respectively.