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  • 1 Centro Universitário do Norte Paulista—UNORP, São José do Rio Preto, SP, Brazil mkobelnik@gmail.com.br
  • 2 Instituto de Química de Araraquara, Unesp—Universidade Estadual Paulista, C.P. 355, Araraquara, SP, 14800-900, Brazil crespims@iq.unesp.br
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Abstract

The Co(II)–diclofenac complex was evaluated by simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC). The DTA curve profile shows one exothermic peak because of the transition phase of the compound between 170 and 180 °C, which was confirmed by X-ray powder diffractometry. The transition phase behavior was studied by DSC curves at several heating rates of a sample mass between 1 and 10 mg in nitrogen atmosphere and in a crucible with and without a lid. Thus, the kinetic parameters were evaluated using an isoconversional non-linear fitting proposed by Capela and Ribeiro. The results show that the activation energy and pre-exponential factor for the transition phase is dependant on the different experimental conditions. Nevertheless, these results indicate that the kinetic compensation effect shows a relationship between them.

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