Artículos de revistas
Study of the thermal behavior in solid state of Mn(II)-Diclofenac complex
Fecha
2018-01-01Registro en:
Ecletica Quimica, v. 43, n. 1, p. 59-66, 2018.
1678-4618
0100-4670
10.26850/1678-4618eqj.v43.1.59-66
2-s2.0-85047903485
7471310113999140
8498310891810082
0000-0002-7984-5908
Autor
Centro Universitário do Norte Paulista (UNORP)
Instituto de Pesquisas Tecnológicas (IPT)
Universidade Estadual Paulista (Unesp)
Institución
Resumen
The preparation, characterization and thermal behavior of Mn(II)-diclofenac solid-state complex was investigated by simultaneous TG/DTA and DTG curves, DSC, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) techniques. The thermal evaluation was carried out with sample masses of 2 and 5 mg, with the purpose of comparing the values of activation energy regarding dehydration, monotropic phase transition and thermal decomposition in both samples mass. The DSC curves were obtained in opened and with crimped lids crucibles of aluminum under oxygen purge gas and static air (without purge gas). The DTA and DSC curves show an exothermic peak between 150-180 °C depending on heating rate, which can be attributed to the monotropic non-reversible reaction. The activation energy (Ea/kJ mol-1) to dehydration, the monotropic phase transition and the first thermal decomposition step were determined by Capela-Ribeiro nonlinear isoconversional method. The activation energy under oxygen dynamic purge gas shows lower values compared to those obtained under static air.