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Oxidized cotton cellulose with COOH contents of 16.0–24.0%, meeting USP requirements, was produced in the HNO3–H3PO4–NaNO2 system. This allowed it to be used as a biodegradable hemostatic agent. The structures of oxidized cotton celluloses were confirmed using IR spectroscopy and elemental analysis and were studied using X-ray diffraction structure analysis. Diffraction patterns of celluloses oxidized for 4–24 h had reflections characteristic of two polymorphic modifications, i.e., cellulose I (characteristic of starting cotton cellulose) and cellulose II. [ABSTRACT FROM AUTHOR]

Structural transformations of potato starch by solutions of nitrogen(IV) oxide in CCl4 were studied as a function of oxidant concentration, starch moisture content, reaction time, and molar ratio of reactants. Oxidized starches with various numbers of carboxylic acids were studied by x-ray phase analysis, 13C NMR, and IR spectroscopy. It was found that carboxylic acids were formed primarily on C6 in starch oxidation products that were x-ray amorphous. The number of carboxyls increased slightly with increased oxidation time and oxidant concentration. It was shown that moisture must be present in the starch for oxidation by nitrogen(IV) oxide to be effective. [ABSTRACT FROM AUTHOR]

Structural transformations of potato starch by solutions of nitrogen(IV) oxide in CCl4 were studied as a function of oxidant concentration, starch moisture content, reaction time, and molar ratio of reactants. Oxidized starches with various numbers of carboxylic acids were studied by x-ray phase analysis, 13C NMR, and IR spectroscopy. It was found that carboxylic acids were formed primarily on C6 in starch oxidation products that were x-ray amorphous. The number of carboxyls increased slightly with increased oxidation time and oxidant concentration. It was shown that moisture must be present in the starch for oxidation by nitrogen(IV) oxide to be effective. [ABSTRACT FROM AUTHOR]