Influence of Chemical Treatment and Moisture Absorption on Tensile Behavior of Neem/banana Fibers Reinforced Hybrid Composites: An Experimental Investigation

Hybrid composites composed of neem fiber (N), banana (B) fiber and epoxy resin were fabricated by hand layup method. Three types of composites with blending ratio of B:N (1:4), B:N (1:1) and B:N (4:1) respectively were fabricated and the effects of fiber loading, chemical treatment and moisture absorption on tensile strength of the composites were investigated. The results showed that the fiber loading influenced the tensile strength and the B:N (4:1) composite displayed the superior tensile strength of 52 MPa compared to other composites due to the presence of more amount of banana fiber with high strength. The B:N (1:4) composite exhibited the lowest tensile strength of 47 MPa owing to the presence of more amount of neem fiber with low strength. Chemical treatment of fiber surface improved the tensile strength significantly due to the removal of impurities, lignin and hemicellulose. Silane-treated composite showed the greater tensile strength compared to alkali treated and untreated composites. Silane treated B:N (4:1) composite exhibited 17.5% and 42.3% improvement in tensile strength compared to the tensile strength of alkali treated and untreated composites respectively. Moisture absorption study revealed that the moisture uptake behavior of composite reduced the tensile strength due to the breakage of H-bond. Moisture absorption reduced the tensile strength of B:N (1:4), B:N (1:1) and B:N (4:1) composites by 14.7%, 10% and 5.8% respectively compared to dry samples.