Thermogravimetric and kinetic study of new bis(iminophosphorane)ethane solvates

Thermal and crystallographic characterization of one solvent-free bis(iminophosphorane)ethane (BIPE) form and three solvates with acetonitrile (ACN), dimethyl sulfoxide (DMSO) and toluene is presented. Thermal behaviors of new compounds indicate that the solvent is removed differently from the BIPE structure, accordingly with the stoichiometric solvent molecule amount incorporated. Thus, the solvent-free BIPE reveals high thermal stability up to 315 °C, while BIPE solvates have a similar pattern behavior with low stability about 130 °C. The kinetic parameters of the thermal decomposition process were determined by three different methods Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose and nonparametric kinetic. Crystallographic data revealed that the solvent plays the role of space filler without strong interactions with host molecules. Guest-free BIPE, BIPE0.5ACN and BIPE0.35DMSO crystallized in monoclinic C2/c (№15) space group, while BIPETOLUENE in a triclinic P - 1 (№2) one. Crystallographic and thermogravimetric data show a good correlation between molecular structures and activation energies.