Production of cellulose nanocrystal (CNC) from papaya tree stem as a potential reinforcement in bionanocomposite manufacturing

Nowadays, to fabricate polyfunctional bionanocomposite CNCs is very attractive to researchers due to its outstanding properties and eco-friendly features. But in general, CNCs are produced from primary plant-derived fibers, which have several advantageous applications in other sectors. Therefore, to diminish the extreme pressure on primary plants, it is crucial to discover alternative sources of CNCs from secondary plants. While the waste biomass of the papaya tree stem would be an innovative and beneficial candidate for the production of CNCs as a reinforcing agent. In this study, dew retting was applied to extract raw fiber from the papaya tree stem then scouring, alkali modification, chlorite bleaching, H₂SO₄ hydrolysis reactions were directed for the production of CNCs. To explore the overall purity and structural belongings of the newly produced CNCs they were categorized by XRD, TGA/DTA/DTG, FTIR-ATR, UV–vis-NIR, FESEM, STEM, EDX, DLS, and zeta potential analysis. The outcomes recommended that the produced CNCs have extensive binding sites, greater thermal stability, higher crystallinity (84.51 ± 0.18 %), well-organized mesoporous honeycomb-like microstructure along with a negative surface charge around −19.30 mV. So, this papaya stem-derived CNCs would be constructively applied as a reinforcement to produce polyfunctional bionanocomposites for various uses in several industrial, engineering, and biomedical sectors.