Characterization and comparison of mechanical behavior of agro fiber-filled high-density polyethylene bio-composites

Abstract

The effects of four agro fibers on the mechanical properties of high-density polyethylene, particle sizes of the fibers, flexural properties, and impact properties of the composites were investigated. Their performances were compared with commonly used wood flour filler. In this research, high-density polyethylene composites filled with agro fiber at high filler content of 65 wt% were prepared. Environment-friendly, sustainable and biodegradable composites were fabricated by melt compounding and extrusion processing technology, using corn cob, rice hull, flax shive, and walnut shell flour with particle sizes distribution 0.295 mm to <0.125 mm as reinforcements for thermoplastics as an alternative to wood fiber. The influence of fiber type and high filler loading level on composite properties was investigated. Mechanical analysis showed that flexural strength, flexural modulus, and un-notched Izod impact strength increased with filler loading at the 65 wt% level for all composites, but there was little difference in both properties among the composites from various fiber types. Bulk density was measured for these agro fiber fillers in relation to wood flour, and the lowest amount was 150 kg/m³. The results of the study demonstrate that agro fiber-filled high-density polyethylene composites can be used as reinforcements for engineering value-added bio-composite materials.