An improved X-ray diffraction method for cellulose crystallinity measurement

摘要

We show in this work a modified X-ray diffraction method to determine cellulose crystallinity index (Crl). Nanocrystalline cellulose (NCC) derived from bleached wood pulp was used as a model substrate. Rietveld refinement was applied with consideration of March-Dollase preferred orientation at the (001) plane. In contrast to most previous methods, three distinct amorphous peaks identified from new model samples which used to calculate Crl. A 2 theta range from 10 degrees to 75 degrees was found to be more suitable to determine Crl and crystallite structural parameters such as d-spacing and crystallite size. This method enables a more reliable measurement of Crl of cellulose and may be applicable to other types of cellulose polymorphs. (C) 2015 Elsevier Ltd. All rights reserved.