Thermal studies of chitin–chitosan derivatives
New poly(azo) amino-chitosan compounds were obtained from the azo coupling reaction of N-benzyl chitosan and diazonium salts. The thermal behavior of these compounds was studied by thermogravimetric analysis (TG), differential thermogravimetric analysis (DTG), TG coupled with a Fourier-transform infrared, and differential scanning calorimetry (DSC). TG/DTG curves of chitin–chitosan polymer showed two thermal events attributed to water loss and decomposition of the polysaccharide after cross-linking reactions. Thermal analysis of the poly(azo) amino-chitosan compounds showed that the decomposition temperatures decreased when compared to the starting chitin–chitosan and N-benzyl chitosan. DSC results showed an agreement with the TG/DTG analyses. Thermal behavior of poly(azo) amino-chitosans suggest that these compounds could be considered as potential thermal sensors.
KeywordsChitin–chitosan biopolymer N-alkylation Azo compounds TG/DTG and DSC
The authors gratefully thank Fundação de Apoio a Pesquisa do Estado de São Paulo (FAPESP), Programa de Pós-graduação em Ciência e Tecnologia de Materiais (POSMAT), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for financial support and post-graduation fellowship.
- 2.Riva R, Ragelle H, des Rieux A, Duhem N, Jerome C, Preat V. Chitosan and chitosan derivatives in drug delivery and tissue engineering. In: Jayakumar RPMMRAA, editor. Chitosan for biomaterials II. Advances in polymer science, 2011. p. 19–44.Google Scholar
- 6.Gopalakrishnan S, Nevaditha NT, Mythili CV. Antibacterial activity of azo compounds synthesized from the natural renewable source, cardanol. J Chem Pharm Res. 2011;3:490–7.Google Scholar
- 7.Manickasundaram S, Kannan P, Hassan QMA, Palanisamy PK. Azo dye based poly(alkyloxymethacrylate)s and their spacer effect on optical data storage. J Mater Sci. 2008;19:1045–53.Google Scholar
- 11.VIII Congresso Brasileiro de Análise Térmica e Calorimetria. III Congresso Pan-Americano de Análise Térmica e Calorimetria. 01–04 April, 2012, Campos do Jordão, São Paulo, Brazil.Google Scholar
- 14.Langhals H. Color chemistry. Synthesis, properties and applications of organic dyes and pigments, 3rd revised edition. Heinrich Zollinger. Angewandte Chemie International Edition. 2004;43:5291–2.Google Scholar
- 15.Kim S. Chitin, chitosan, oligosaccharides and their derivatives, biological activities and applications. USA: CRC Press; 2011. p. 149–66.Google Scholar