Characteristics and Properties of Cellulose Nanofibers Prepared by TEMPO Oxidation of Corn Husk

This paper describes preparation of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) mediated oxidized cellulose nanofibers (TOCNs) from corn husk. The process adopted for this work included alkaline treatment, TEMPO/NaBr/NaClO-mediated oxidation, and homogenization. The morphological investigation of TOCNs was performed using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The chemical composition and structure of the material obtained after each stage of the treatments was characterized through Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. The thermal stability of the samples was investigated by thermogravimetric analysis (TGA). The obtained TOCNs possessed a narrow width, ranging from 8 to 10 nm, and a high aspect ratio (> 300). The crystallinity type of TOCNs was found to be cellulose-Iβ. Compared with the original fibers, the crystallinity of TOCNs gradually increased because of the removal of hemicellulose and lignin, while the thermal stability decreased.