Study of the chemical structure of dialdehyde carboxymethyl cellulose produced by periodate oxidation under different conditions

13C nuclear magnetic resonance, paramagnetic resonance, and ultraviolet spectroscopy and highresolution gel permeation chromatography were used to investigate the process of periodate oxidation of carboxymethyl cellulose and the structure and molecular weight characteristics of its oxidised forms produced under different conditions. It was shown that, in solution and in the solid state, aldehyde groups in the oxidised units exist in the form of cyclic hemiacetals. An examination was made of the existence of all the main cyclic intramolecular hemiacetal structures, and the most probable were proposed. The influence of the degree of periodate oxidation on the molecular weight characteristics and hydrolytic stability of dialdehyde carboxymethyl cellulose was studied.