Isolation and Characterization of Cellulose Nanocrystals from Waste Cotton Fibers Using Sulfuric Acid Hydrolysis
Soraya Soleimani, Amir Heydari, Moslem Fattahi
Abstract
Abstract Cellulose nanocrystals (CNCs) are one of the most useful materials that have recently been used in various fields. There are many natural resources on earth from which CNC can be extracted in a variety of methods. This study focuses on the extraction of CNCs from waste cotton fibers (WCFs) by sulfuric acid hydrolysis. Physicochemical characterization of the synthesized CNCs was examined by different techniques. The results revealed good performance and properties for synthesized CNCs. Fourier transform infrared spectroscopy (FTIR) analysis demonstrated the successful synthesis of CNCs by acid hydrolysis without the formation of byproducts or further degradation. X‐ray diffraction (XRD) analysis showed that the crystallinity index increased from 79.87 to 88.37% during the conversion of WCFs to CNCs. The rod‐like morphology structure of CNC was confirmed using microscopic techniques. The AFM results for CNCs showed a length and diameter of 170 ± 60 nm and 25 ± 10 nm, respectively. Also, DLS measurements showed high stability of CNCs in aqueous solution. Moreover, due to the presence of 0.74 weight% of sulfur in the CNC backbone, CNCs showed lower thermal stability at 170–348 °C compared to WCFs.