The use of DSC curves to determine the acetylation degree of chitin/chitosan samples

Autor(es)

Cavalheiro, Éder Tadeu Gomes ; Guinesi, Luciana Simionatto ^[2]

• Tipo de documento: Artigo Científico
• Fonte: Thermochimica Acta; v. 444, n. 2, p. 128-133, May 2006.
• Área do conhecimento: Ciências Exatas e da Terra - Química
• Assunto(s): Acetilação Quitosana Quitina

Resumo

The use of DSC curves is proposed as an alternative method to determine the degree of N-acetylation (DA) in chitin/chitosan samples, based in both peak area and height of the decomposition signal. Samples with DA from 74 to 16% were prepared from a chitin commercial sample and the DA was determined by 1H NMR, 13C CP/MAS NMR and IR spectra. The effect of water content, heating rate, sample mass and gas flow on the DSC peaks were evaluated and optimized. Using optimized conditions a linear relationship between peak area and height with the DA could be achieved with linear correlation coefficients of −0.998 and −0.999 (n = 7), respectively. The calibration graphs were used to determine the DA of a commercial chitosan sample with relative errors ranging from 2 to 3% for both peak area and peak height, when compared with the DA determined by 1H NMR method. (AU)

• Processo FAPESP: 03/09224-7 - Estudo termoanalítico e cinético de quitosanas modificadas com Bases de Schiff em diferentes graus de acetilação e substituição
• Beneficiário: Luciana Simionatto Guinesi
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 02/03448-8 - Estudos termoanalíticos de biopolímeros, ditiocarbamatos e derivados de ácidos graxos
• Beneficiário: Éder Tadeu Gomes Cavalheiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular