Abstract

The thermal stability seems to depend on the kind of bond established between the chitin and the reactant. Tosylate exhibits the lowest Ea. probably due to its property as a good leaving group. Furthermore, chitin-acetate has the highest Ea due to its similarity with the pendant group which enables the macromolecule to achieve better electric resonance stabilization. The thermal stabilities of copper and tin films containing various organic solvents have been studied by thermogravimetry (TG) between 298 and 823 K under a flow of nitrogen. The thermal stabilities of the Cu films decrease in the order Cu-THF > Cu-DMF > Cu-toluene > Cu-ethanol > Cu-acetone > Cu-2-butanone > Cu-benzene, Cu-2-propanol > Cu-DMSO. On the other hand, the organotin films exhibit a decreasing stability in the following order: Sn-2-propanol > Sn-ethanol > Sn-acetone > Sn-2-butanone, > Sn-benzene > Sn-DMF, Sn-DMSO > Sn-toluene. This suggests that the solvent incorporated into the film has a considerable influence on the stability, in that solvents containing oxygen are very stable and have a comparatively high thermal decomposition temperature (Td) and low residual weight. The order of the thermal decomposition reaction was found to be zero in most of the cases. The pre-exponential factor and the activation energy of the decomposition of Cu and Sn metal films are also compared.