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Use of Microwave Heating in the Synthesis of Novel Polysaccharide Derivatives.
Taubner, T. ; Synytsia, A. ; Sobek, Jiří ; Kortanková, V. ; Čopíková, J.
Microwave-assisted modification of polysaccharides is a relatively new method. Microwave heating is used for improving of extraction, hydrolytic and synthetic procedures. Modification of polysaccharides with the microwave irradiation is effective, fast and economic. The aim of this study was to apply the microwave irradiation in synthesis of carboxymethylcellulose (CMC) derivatives. This polysaccharide and its methyl ester reacted with n-butylamine yielding N-butylamide. The reactions were subsequently monitored by FUR and organic elemental analysis of the products. Degree of substitution (DS) and reaction yields were calculated based on nitrogen and carbon contents. The optimal reaction conditions were found to prepare product with the highest DS. Amino-de-alkoxylation of CMC methyl ester was significantly more effective than direct microwave assisted amidation of CMC, and microwave assisted significantly improved amino-de-alkoxylation.
Fulltext: content.csg -  PDF
Plný tet: Proceedings of the ... Tauber, T._Use of microwave - PDF
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Preparation of Amide Derivatives of Oxidized Cellulose and Carboxymethylcellulose
Taubner, T. ; Synytsya, A. ; Sobek, Jiří ; Čopíková, J.
This work is focused on the preparation of amide derivatives of oxidized cellulose and carboxymethyl cellulose. Research involved the preparation of derivatives in two steps and the first preparation of a methyl ester of the starting polysaccharide, and then aminodealkyxilation with selected primary alkylamines, ethanolamine, ethylenediamine, hydrazine and hydroxylamine. Another part of the research included the direct amidation without intermediate steps starting polysaccharide preparation of methyl ester using the same reagents and support of microwave radiation. The obtained products were monitored by FT-IR spectroscopy and organic elemental analysis.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22012043014260 - PDF
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Deriváty oxidované celulozy
Taubner, T. ; Sobek, Jiří ; Havelka, P. ; Kvasnička, F. ; Synytsya, A. ; Čopíková, J.
The reactivity of Na and salt of oxidized cellulose and its oligosaccharides with chitosan will be presented. Hydrolysis of Na and salts of oxidized cellulose was carried out in homogenous system by means with microwave irradiation at constant conditions. The reaction progress was monitored by capillary isotachophoresis and size exclusion chromatography. Reactivity of oxidized cellulose or its hydrolysates with NH2 groups of chitosan was promoted by MW irradiation. Reaction was monitored by infrared spectroscopy.
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