Synthesis, Vibrational Spectroscopic and Thermal Properties of Oxocarbon Cross‑Linked Chitosan

• Autor(a) principal: Souza,Nelson L. G. D.
• Data de Publicação: 2015
• Outros Autores: Salles,Tamyres F., Brandão,Humberto M., Edwards,Howell G. M., Oliveira,Luiz F. C. de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532015000601247
• topic: chitosan; crosslinking; oxocarbon; infrared and Raman; solid state 13C NMR

In this work specimens of chitosan which have been cross-linked covalently and ionically with different oxocarbon and pseudo-oxocarbon anions have been synthesised and characterized using infrared and Raman spectroscopic techniques, solid state 13C nuclear magnetic resonance (NMR) and by thermogravimetry. According to the spectroscopic and thermal results, ionically crosslinked chitosans are obtained with squarate, croconate and rhodizonate ions as crosslinking agents, whereas covalently crosslinked chitosan can be obtained when squaric acid is used as the crosslinking agent; the same products are not observed when the pseudo-oxocarbon anion croconate violet is used, which can be attributed to the low basic strength of the crosslinking species.