Swelling of Valonia cellulose microfibrils in amine oxide systems
| Autor: | Henri Chanzy, Pierre Noé |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
0303 health sciences
Valonia ventricosa biology Organic Chemistry General Chemistry Valonia 010402 general chemistry biology.organism_classification 01 natural sciences Catalysis 0104 chemical sciences 03 medical and health sciences chemistry.chemical_compound chemistry Electron diffraction Chemical engineering Transmission electron microscopy Polymer chemistry medicine Ultrastructure Cellulose Swelling medicine.symptom Dissolution 030304 developmental biology |
| Zdroj: | Canadian Journal of Chemistry. 86:520-524 |
| ISSN: | 1480-3291 0008-4042 |
| DOI: | 10.1139/v08-030 |
| Popis: | Cellulose microfibrils from Valonia ventricosa cell-wall fragments were immersed into molten N-methylmorpholine-N-oxide monohydrate (NMMO·H2O), stabilized with n-propyl gallate and kept at 80 °C. The resulting ultrastructural modifications, which were followed by transmission electron microscopy and electron diffraction analysis, showed that within minutes the solvent slowly penetrated inside the crystalline microfibrils and progressed as a wedge in between the cellulose chains without cutting them. Prior to dissolution, a longitudinal subfibrillation of the initial microfibrils occurred, leading to the observation of highly swollen microfibrils, which could reach diameters up to three times larger than those of the initial samples. This mode of swelling is compared with those occurring in other systems, where the intracrystalline swelling of cellulose has been described at the ultrastructural level.Key words: cellulose swelling, Valonia cellulose, N-methylmorpholine-N-oxide. |
| Databáze: | OpenAIRE |
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