Thermal analysis in oxidative and pyrolysis conditions of alkaline earth metals picolinates using the techniques: TG-DSC, DSC, MWTA, HSM and EGA (TG-DSC-FTIR and HSM-MS)

Abstract

Synthesis, characterization, thermal stability and pyrolysis of some alkaline earth picolinates M(C6H5NO2)2nH2O (where M = Mg(II), Ca(II), Sr(II) and Ba(II) and n = di (Mg), mono (Ca), hemi three (Sr) hydrated) were investigated using a range of techniques including simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), evolved gas analysis (EGA), differential scanning calorimetry (DSC), Hot-Stage microscopy (HSM), powder X-ray diffractometry (PXRD), complexometry with EDTA and elemental analysis (EA). The TG-DSC curves show that the hydrated compounds dehydrate in a single step of mass loss and the thermal stability of the anhydrous compound is little influenced from the atmosphere used. On the other hand, the mechanisms of thermal decomposition are profoundly influenced by the atmosphere used, as can also be observed in the EGA data. In addition, a comparison between two calorimetric techniques, Microwave Thermal Analysis (MWTA) and DSC, was made which showed similar profiles. Two evolved gas analysis (EGA) techniques: TG-DSC coupled to FTIR and HSM coupled to a quadrupole mass spectrometer (MS) were also used to provide additional information about the pyrolysis mechanism.

Lornoxicam drug—A new study of thermal degradation under oxidative and pyrolysis conditions using the thermoanalytical techniques, DRX and LC-MS/MS

“…In addition, identifying the thermal degradation products may support studies of forced degradation of the drug [10]. Thermal analysis coupled with techniques such as mass spectrometry and infrared spectroscopy has been widely used to understand the mechanisms of thermal decomposition, allowing the assignment of the products produced in the reactions [7][8][9][10][11][12].…”

Barbier polymerization towards synthesizing polar polyolefin analogues for polyolefin modification

“…Differential scanning calorimetry (DSC) testing is primarily used to reflect the enthalpy changes that occur in a sample as the temperature varies. 39,40 It can provide insights into the glass transition temperature, crystallinity, and melting behavior of the tested samples. Both LLDPE and HPBP/LLDPE samples were subjected to heating and cooling processes for DSC testing.…”

Study of rhombohedral tricalcium phosphate in hexagonal crystal structure family on the sample prepared by the sol-gel route and the effect of calcination temperature

“…9d). This result indicated the crystalline structure of the sample was changed as a function of temperature and the chemical bond changed when heat flowed in (absorbed by the endothermic process) or out (released by the exothermic process) [43,44]. Table III shows the results of initial, T i , and final, T f , melting or fusion temperatures, enthalpy of fusion, ΔH F , and crystallization, ΔH C , and specific heat capacity, C P .…”