Reuse of waste cotton cloth for the extraction of cellulose nanocrystals.

Cellulose nanocrystals (CNCs) were prepared from waste cotton cloth and degreasing cotton was used as a comparison. The cellulose was first extracted by alkali and bleaching treatments, and then the CNCs were isolated by the mix acid solution hydrolysis of cellulose under the controlled conditions. The CNCs were analyzed by Attenuated total reflectance Fourier transform infrared spectroscopy, Transmission electron microscopy, X-ray diffraction analysis, thermogravimetric and differential scanning calorimetry analysis. The results confirmed that the resultant samples were the cellulose species, and the CNCs obtained from waste cotton cloth exhibited a high crystallinity index of 55.76±7.82%, which had higher thermostability than that from the degreasing cotton. The morphology analysis results showed that the ranges of length and diameter of CNC extracted from waste cotton cloth were from 28 to 470nm and 3 to 35nm. The preparation of CNCs with a high aspect ratio and good thermostability in this work paves the way for an alternative reuse of waste cotton cloth.