Properties of cellulose nitrates produced by nitration of bacterial cellulose using mixed sulfuric-nitric acids

• Published in: Proceedings of Universities. Applied Chemistry and Biotechnology Vol. 14; no. 2; pp. 236 - 244
• Main Authors: Gorbatova, P. A., Korchagina, A. A., Gismatulina, Yu. A., Shavyrkina, N. A., Budaeva, V. V.
• Format: Journal Article
• Language: English
• Published: 07.07.2024
• DOI: 10.21285/achb.915
• ISSN: 2227-2925

    The study set out  to investigate the chemical functionalization of bacterial cellulose as an alternative means of satisfying the high demand for nano-sized cellulose nitrates.    Using a Medusomyces gisevii Sa-12 symbiotic culture as a microbial producer, bacterial cellulose having a polymerization degree of 3950 was obtained on a synthetic glucose medium. Nitration was carried out using mixed sulfuric-nitric acids differing in their water content, followed by stabilization of the synthesized bacterial cellulose nitrates. Subject to a varying water content (14, 16 and 20 %) in the nitrating mixture, the obtained bacterial cellulose nitrates exhibited a nitrogen mass content of 8.68–11.56 %, a solubility in alcohol-ether mixture of 16.5–91.0 % and a viscosity of 32–255 mPa×s. The bacterial cellulose nitrate fibers were shown to have a nanoscale nature. Coupled thermogravimetric and differential thermal analyses revealed the bacterial cellulose nitrates to have a high chemical purity and energy content. FTIR spectroscopy confirmed the high quality of the bacterial cellulose based on the presence of basic functional groups characteristic of conventional cellulose: 3371, 2943, 1633, 1428, 1371, 1163, and 1112 cm -1 . According to their infrared spectra, the detected basic functional groups corroborate that the synthesized products are low-substituted cellulose nitrate esters: 1660–1643, 1282-1276, 847–837, 752–749, and 691–690 cm -1 . The relationship between the properties of the synthesized bacterial cellulose nitrates and the water mass content in mixed sulfuric-nitric acids is shown to have a complex nature.