Improvement of mechanical and interfacial properties of hot water and sodium bicarbonate treated jute fibers for manufacturing high performance natural composites

Uses of natural fibers in the field of composites are often restricted by their poor mechanical and interfacial properties. Fiber constitutions have significant influence over both of these properties. Traditional alkali treatment is mainly used to solve this problem which is not environmentally friendly and also not cost effective. A cost effective, less hazardous and sustainable sodium bicarbonate chemical treatment has been used as an alternative of traditional mercerization on jute fibers with an objective of manufacturing high-performance natural fiber composites. Jute fibers were hand combed and treated with hot water and bicarbonate (5% and 10%) and further reinforced with epoxy resin to make composites. The mechanical characterizations of jute fiber were carried out using single fiber tensile tests; reliability analysis of the experimental data was performed. Interfacial adhesion of jute fiber with an epoxy matrix was investigated by using single fiber pull-out techniques. The mechanical behavior of jute fiber/epoxy composites was studied by flexural testing. FTIR analysis indicates that sodium bicarbonate treatment can progressively remove hemicellulose and reduce the content of lignins present in the fiber. The results also showed that a 10% sodium bicarbonate concentration increased the tensile properties of jute fiber, enhanced the interfacial shear strength and flexural properties of jute/epoxy composites.