Predicting the Shelf Life of Energetic Materials via Kinetic Analysis of Decomposition Data Gathered by Using Thermal Analysis Techniques

The shelf life of energetic materials (EMs) (i.e., explosives, propellants, and pyrotechnics) is strictly linked to safety and functionality. Therefore, a priori knowledge of this parameter is of paramount importance. The standard method for predicting the shelf life of EMs, the so called multi temperature aging method, is tremendously time and money consuming. Specifically, it consists of massive isothermal accelerated aging tests at temperatures typically between 40 and 80°C for relatively long time periods (from months to years) with different aging time intervals, followed by analysis of the aging-induced changes. A subsequent kinetic analysis with Arrhenius evaluation provides the effective activation energy for calculating shelf life at lower storage temperatures. In this work, a much less time- and resource-intensive approach is presented as a possible alternative for the shelf life prediction of EMs. This approach is based on the kinetic analysis of decomposition data gathered by using thermal analysis techniques, which are usually operated under dynamic (i.e., non-isothermal) conditions and possess the advantage of a rapid reaction process, and requires accelerated aging tests only to validate the kinetics extracted from such data. Results from the literature to support this alternative approach are discussed, with particular emphasis on those obtained by the present authors.