Preparation and thermal study of Mg-diclofenac compound in solid state

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The thermal behaviour of Mg-diclofenac compound was evaluated by simultaneous TG-DTA and DSC. The profile of the DSC curves showed that this compound possesses two transition phases: endothermic and exothermic between 170-180 degrees C and 185-195 degrees C, respectively. The endothermic reaction is reversible (enantiotropic). Thus, different experimental conditions, i.e. masses sample, open and crimped lids crucible, static and dynamic atmospheres were utilized for DSC analysis for evaluation of this transition phase. In a static atmosphere the enantiotropic reaction was not observed. The obtained data were utilized to obtain the kinetic parameters, which were calculated by the Capela and Ribeiro method. The results show that the activation energy for the transition phase depends on the different experimental conditions.