Facile Acid Hydrolysis of Cotton-Based Cellulose: Obtaining Cellulose Nanocrystals and Investigating Dispersion Their Properties via a Refractometric Method

Over recent decades there has been a significant surge in research interest aimed at developing novel composite materials derived from cellulose, catering to the diverse needs of industries such as paper, pharmaceuticals, and medicine. Aligned with this trend, our research project described here focused on leveraging cellulose to produce high-value-added products, particularly nanocomposite materials for reinforcement purposes. Our aim was to develop nanocomposite materials utilizing hydrolyzed cotton cellulose. To begin with we employed a straightforward, cost-effective and readily applicable process to extract nanocellulose from cotton fibers. The structural integrity of the resulting cellulose nanocrystals (CNCs) was validated through various analytical methods such as UV-visible spectroscopy, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), thermogravimetric analyses (TGA), differential scanning calorimetry (DSC) and Raman spectroscopy. We conducted a comprehensive examination of the physicochemical properties of the CNCs, particularly investigating their dispersion behavior and solubility in both aqueous and selected organic solvents. In the final phase of our study, we explored the chemical modification of CNCs using maleic anhydride to produce cellulose maleate. The structural transformation was confirmed through infrared spectroscopy (FTIR) analysis.