Non-isothermal kinetic study of the thermal decomposition of N-{bis[benzyl(methyl)amino]phosphoryl}-2,2-dichloroacetamide and N-{bis[dibenzylamino]phosphoryl}-2,2-dichloroacetamide

摘要

In this paper, the thermal behaviours of N-{bis[benzyl(methyl) amino]phosphoryl}-2,2-dichloroacetamide (BMA) and N-{bis[dibenzylamino]phosphoryl}-2,2-dichloroacetamide (DBA) were studied by thermogravimetery (TG) and differential scanning calorimetery (DSC) techniques under the non-isothermal conditions. The results showed that BMA melts about 120 °C before it decomposes. BMA decomposition occurs in three continuous steps, in the 170–400 °C temperature range. Each thermal degradation stage for BMA results an exothermic peak in the DSC curve. On the other hand, applying TG-DSC techniques indicates that DBA melts about 175 °C before it decomposes. This compound decomposes in the temperature range of 200–600 °C in three steps. Activation energy and pre-exponential factor for each compound were found by means of Kissinger method and were verified by Ozawa–Flynn–Wall method. Activation energy obtained by Kissinger method for the first stage of BMA and DBA decompositions are 151.8 (±2.0) KJ mol?1 and 138.7 (±2.6) KJ mol?1, respectively. Finally, the thermodynamic parameters (ΔG #, ΔH # and ΔS #) for first step decomposition of DBA and BMA were determined.