Effect of compatibilizer and fiber loading on ensete fiber-reinforced HDPE green composites: Physical, mechanical, and morphological properties

Ensete fiber is a natural material extracted from E. ventricosum plants which is widely cultivated for food. This study is the first attempt to develop its composite by improving its compatibility with high density polyethylene (HDPE). The premixed composite constituents were melt-compounded by twin-screw extrusion and granulated. Composite plates were molded using hot-press machine. The effect of grafting maleic anhydride to HDPE and varying fiber loading on composite properties were investigated. Increasing ensete fiber loading has resulted in the composites being stiffer and harder leading to a decrease in its elongation at break. The addition of 5 wt% compatibilizer into 25 wt% ensete fiber-filled HDPE improved the fiber-matrix adhesion. Its tensile strength, flexural strength and impact absorption energy increased by nearly 43%, 46%, and 56% respectively when compared to composites with the same fiber loading and without compatibilizer. Morphological analysis from microscopic images of tensile fracture surfaces enlightened the interfacial adhesion to support these test results. The composites density, water absorption and melt flow index were also compared. The results show that ensete fiber-HDPE composite could be used as construction and building materials, low-density furniture, and moldable structures in need of design flexibility.