Thermal properties and stability of cassava starch films cross-linked with tetraethylene glycol diacrylate
LE MEINS, Jean-Francois
Laboratoire de Chimie des polymères organiques [LCPO]
Team 3 LCPO : Polymer Self-Assembly & Life Sciences
< Réduire
Laboratoire de Chimie des polymères organiques [LCPO]
Team 3 LCPO : Polymer Self-Assembly & Life Sciences
Langue
en
Article de revue
Ce document a été publié dans
Polymer Degradation and Stability. 2006, vol. 91, n° 4, p. 726-732
Elsevier
Résumé en anglais
The thermal stability of starch cross-linked with tetraethylene glycol diacrylate was studied under nitrogen atmosphere by thermogravimetry (TG) and infrared spectroscopy (FTIR). The cross-linking reaction was confirmed ...Lire la suite >
The thermal stability of starch cross-linked with tetraethylene glycol diacrylate was studied under nitrogen atmosphere by thermogravimetry (TG) and infrared spectroscopy (FTIR). The cross-linking reaction was confirmed by the increase in intensity of the absorption band at ca. 3330 cm(-1) indicating the reinforcement of hydrogen bonds and the appearance of a new band at 1726 cm-1 associated with the carbonyl group of the cross-linking agent. After cross-linking the solubility of starch in water decreased to the range 9%-16%. The thermogravimetric curves of pure and cross-linked starches showed an initial stage of degradation (up to ca. 150 degrees C) associated with the loss of water. The main stage of degradation occurred in the range 250-400 degrees C corresponding to ca. 60%-70% mass loss. The activation energy (E) for the degradation process increased from 145 kJ mol(-1) (pure starch) to 195 kJ mol(-1) and 198 kJ mol(-1) for starch treated for 60 min by UV (30 degrees C) and at 90 degrees C, suggesting high stability after cross-linking. A higher value (240 kJ mol(-1)) was obtained for starch treated by UV for 120 min. The main volatile products determined by FTIR which correspond to hydrocarbons and carbonyl groups are apparently associated with the scission of weak bonds in the chain (probably branched groups) and the scission of stronger bonds (glycosidic linkages), respectively.< Réduire
Mots clés en anglais
activation energy
cross-linking effect
cassava starch
thermal stability
Origine
Importé de halUnités de recherche