Abstract
In this paper structural characteristics and properties of cellulose and its nitrogenated derivatives – chitin and chitosan, have been studied. The obtained results showed that substitution of hydroxyl group in C2 of anhydroglucose unit of cellulose on nitrogen-containing groups leads to transformation of crystalline unit cell, increasing of interplanar distances and cell volume, and reduction of packing density of crystallites. Since cellulose contains lesser amounts of atoms C and H, the combustion of this polysaccharide requires lower oxygen amount than of nitrogenated derivatives; as a result, the exothermic value of combustion enthalpy increases when going from cellulose to chitosan and chitin. Study of hydrophilic properties revealed that wetting enthalpy and sorption of water vapor depend on the degree of amorphicity (Y) of the biopolymers. At the same Y-value the hydrophilic properties of cellulose and chitosan containing hydroxyl or amino groups were higher than of chitin containing hydrophobic acetyl groups. In the sequence: cellulose-chitin-chitosan, an increase in hydrolyzability of the biopolymer samples was observed. Furthermore, three methods for determination of degree of crystallinity and amorphicity such as X-ray, calorimetry and sorption, were discussed.

Keywords
Cellulose, Chitosan, Chitin, Structure, Crystallinity, Amorphicity, Thermodynamic properties, Hydrophility, Hydrolyzability

Cite this paper
Michael Ioelovich, COMPARATIVE STUDY OF CELLULOSE AND ITS NITROGENATED DERIVATIVES , SCIREA Journal of Chemistry. Volume 1, Issue 1, October 2016 | PP. 1-15.

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