Extraction and characterization of cellulose nanofibres and cellulose nanocrystals from Sammaz-14 maize cobs

Abstract

This article investigated the utilization of the Sammaz-14 variety of maize (Zea mays spp.) cobs for the isolation of nanocelluloses through chemical and mechanical methods. The extracted nanocelluloses were characterized by particle size analysis (PSA), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD). Morphological analysis was performed through Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscopy (AFM), whereas energy disperse X-ray (EDX) was used to determine the elemental composition. The isolated maize cob nanocrystals (MC-NC) and maize cob nanofibres (MC-NF) were obtained in nanoscale, as shown by PSA. Thermal analysis showed that MC-NF is more thermally stable when compared to MC-NC. FTIR revealed identical spectrums for MC-NC and MC-NF with minor deviation from the MC-UT due to the elimination of the 1700 cm−1 peak. Morphological studies showed MC-NC and MC-NF have needlelike structures, while the untreated maize cob (MC-UT) is plain due to the amorphous portion. MC-NC has higher crystallinity of 78% compared to 61% for MC-NF and 40% for MC-UT.