Preparation of the Ca-diclofenac complex in solid state

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The Ca-diclofenac compound was prepared. Thermogravimetry (TG), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC), X-ray diffraction powder patterns, and microscopy analysis were used to characterize this compound. Details concerning the stages of dehydration, transition phase, and thermal decomposition as well as data of the kinetic parameters of these stages have been described here. The kinetic study of these stages was evaluated from several heating rates with a sample mass of 2 and 5 mg in open crucibles under nitrogen atmosphere. The obtained data were evaluated with the isoconversional kinetic method, where the value of activation energy (E (a)/kJ mol(-1)) was evaluated in function of the conversion degree (alpha). The results show that this compound is hygroscopic. The obtained data lead to a dependence on the sample mass, which results in two kinetic behavior patterns.