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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]

Cationization of wood and cotton celluloses using 3-chloro-2-hydroxypropyltrimethylammonium chloride in aqueous suspensions in the presence of various amounts of NaOH followed by cross-linking with epichlorohydrin was studied in detail. The compositions of the cationic cellulose ethers and the reaction efficiency depended strongly on the ratio of the alkylating mixture components. The physicochemical properties of the synthesized samples were studied using chemical analysis, IR spectroscopy, X-ray structure analysis, and centrifugation to determine water absorption. The content of cationic groups and concentration of cationic cellulose in the epichlorohydrin cross-linking stage had decisive effects on the degree of swelling in water and aqueous NaCl solution of the cross-linked cationic cotton and wood celluloses. [ABSTRACT FROM AUTHOR]

The reaction kinetics of an aqueous suspension of potato starch, various amounts of NaOH, and cationic 3-chloro-2-hydroxypropyltrimethylammonium (chloride) were studied in detail. It was found that the compositions of the sparsely substituted cationic starch ethers and the efficiency of the reaction depended strongly on the ratio of components in the alkylating mixture. The physicochemical properties of the synthesized samples were studied using chemical analysis, scanning electron microscopy, x-ray structure analysis, and thermogravimetry. It was shown that the temperature regime of the reaction had a determining influence on the thermal stability and structural changes of the cationic starch derivative. [ABSTRACT FROM AUTHOR]

Chemical modification of potato carboxy starch in the sodium pyrosulfate-dimethyl sulfoxide system was studied with the aim of preparing water-soluble highly substituted sulfo esters. The dependence of the degree of sulfo group substitution on the reaction conditions was studied in detail. The optimal conditions ensuring formation of water-soluble sulfo esters of carboxy starch with the maximal sulfur content were determined. The carboxy starch sulfo ester samples synthesized were characterized by elemental analysis, IR and 13C NMR spectroscopy, and high-performance exclusion chromatography. [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]