Investigation of the most effective molecular descriptors on the thermal behaviour of energetic azido-ester plasticizers through QSPR approach

In this work, the most effective molecular descriptors on the thermal behaviour of energetic azido-ester plasticizers are investigated through quantitative structure–property relationship approach. At first, a new simple and reliable correlation is developed for predicting thermal decomposition temperature (T_d) of energetic azido-ester plasticizers through multiple linear regression method. The determination coefficient of the derived correlation is 0.950, and it has root mean square deviation (RMSD) and average absolute deviation (AAD) of 2.74 and 2.09 °C, respectively. The internal and external validation method is shown that the developed correlation has good predictive ability. Then, the relationship between glass transition temperature (T_G) of energetic azido-ester plasticizers and their T_d is studied. This study shows that the optimum elemental composition, number of ester groups, number of azido groups and the presence of aromatic fragments are the important molecular descriptors as well as several non-additive structural parameters which have significant effect on the thermal behaviour of energetic azido-ester plasticizers. The determination coefficient of this correlation is 0.971, and it has RMSD and AAD of 3.70 and 2.67 °C, respectively. These results could be used to design ideal energetic azido-ester plasticizers.