Development of quantitative structure-property relationship (QSPR) models for predicting the thermal hazard of ionic liquids: A review of methods and models

Ionic liquids (ILs), or ambient-temperature molten salts, comprise ions solely and exhibit several specific liquid-like properties. Research in this area has developed promptly and extensively. Sufficient thermal stability is required when ILs are applied as electrolytes, fire retardants, catalysts, or solvents. Because the thermal decomposition temperature (T_d) indicates the maximum processing temperature before undergoing chemical decomposition, it is among the most crucial parameters characterizing their thermal hazard. Apart from actual experimentation, the quantitative structure-property relationship (QSPR) methods have already been applied in forecasting the T_d of ILs. In this paper, the possible means of structurally characterizing ILs are comprehensively reviewed. Advances in the QSPR method for predicting IL properties are highlighted, and existing models predicting the T_d of ILs are presented. The need for developing new interaction descriptors of ILs for future applications is also emphasized.