Physico-mechanical, Chemical Composition and Thermal Properties of Cellulose Fiber from Hibiscus vitifolius Plant Stalk for Polymer Composites

In the present work, physico-mechanical, chemical composition, and thermal properties of cellulosic fiber extracted from the stem of Hibiscus vitifolius plant have been investigated. The wide characterization was conducted on the Hibiscus vitifolius (HV) fibers and the results proved their potentials for composite applications. Characterization tests on HV fibers confirmed the chemical constituents such as cellulose (75.09 wt. %), lignin (10.42 wt. %), hemicelluloses (13.34 wt. %), wax (0.17 wt. %), ash (0.94 wt. %) and moisture content (11.31 wt. %). The density of HVFs was found to be 1530 kg/m3. X-ray diffraction analysis of HVFs revealed 67.07% crystallinity index and 2.09 nm crystallite size. Tensile strength and percentage of elongation at failure exhibited by HVFs examined through single fiber tensile test was found to be 224.32–716.70 MPa and 3.99–8.77%. Thermo gravimetric analysis revealed thermal stability of HVFs up to 260°C with kinetic activation energy of 126.86 kJ/mol. Cellulose with high crystallinity index, lower wax content, good tensile resistance and better thermal behavior make HV fibers more suitable for composite manufacturing. The morphology of fiber surface studied through SEM images revealed the presence of more roughness at the outer surface which can improve the fiber-matrix bonding during composites preparation.