HEAT TREATMENT TO MODIFY THE STRUCTURAL AND PHYSICAL PROPERTIES OF CHITOSAN-BASED FILMS (DOI: 10.1021/jf204077k)

RIVERO, S; GARCÍA, M.A.; PINOTTI, A.

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

AMER CHEMICAL SOC

Año: 2012 vol. 60 p. 492 - 499

0021-8561

DOI: 10.1021/jf204077k This work was focused on studying the changes undergone by heat treated chitosan films with and without tannic acid addition chitosan-based films by monitoring both microstructure and physical properties. Once the films were submitted to different heat treatments, they exhibited higher barrier properties as well as lower water uptake, solubility and moisture content. These results were also confirmed through X-Ray patterns, which changed from the hydrated to the anhydrous conformation, sharper FTIR peaks specifically associated to water and shift of Tg towards higher temperatures determined by DMA. Moreover, the modifications caused by the curing process at a molecular scale were observed at a structural level by using TEM technique. FTIR evaluation allowed attaining new insights into the interactions between tannic acid and chitosan molecules, before and after the heat curing, especially due to the occurrence of new peaks and changes in the wavenumber region 1550-1750 cm-1.