Production of cellulose nanocrystals from the waste banana (M. oranta) tree rachis fiber as a reinforcement to fabricate useful bionanocomposite

It is crucial to produce CNCs from the waste biomass of secondary plants to reduce the extra pressure on primary plants which have other advantageous applications in many sectors. Whereas the useless banana (M. oranta) rachis after harvesting its edible part could be a very new and beneficial one. Meanwhile, several well-known methods could be conducted, namely water retting, scouring, alkali treatment, chlorite bleaching, and acid hydrolysis, to yield high-quality CNCs. The samples of all stages were characterized by several state-of-the-art techniques, namely FTIR-ATR, TGA, FESEM, XRD, UV–vis-NIR, DLS, and zeta potential analysis, for a better understanding of their structural properties/purity. However, obtained results recommended that the CNCs have shown extensive active edges, greater thermal improvement up to 700 °C, high crystallinity around 81.07±0.15% with JCPDS-ICDD card number (00-056-1718), a honeycomb-like porous microstructure, and promising spherical shapes along with an average size around 50 nm. Additionally, the newly produced CNCs were free from all impurities and coloring materials and revealed a higher negatively charged surface around -45 mV. Therefore, due to these outstanding features, banana rachis CNCs with a high yield (around 82.05±0.06%) would be beneficially used as promising reinforcement to fabricate useful bionanocomposite for various applications to replace fossil-based hazardous synthetic materials.