Progress in Energy−Safety Balanced Cocrystallization of Four Commercially Attractive Nitramines

In 2011, cocrystallization of energetic materials became a hot topic and a pathway to overcome the energy−safety contradiction; especially for commercially attractive nitramines, it became the first preference for researchers. The present review focuses on the energetic−energetic cocrystallization of four commercially attractive nitramines, CL20, HMX, BCHMX, and RDX, the structural aspects of these cocrystals, and their influence on thermochemical and detonation properties. Cocrystallization has proven to be a crystal engineering technique to achieve the safety and morphological suitability of energetic−energetic cocrystals (EECCs). Overall, in most of the cases, the impact sensitivities of EECCs are decreased, and this is a phenomenal change; however, it needed to adjust with detonation properties slightly, and it is negligible if the coformer energetic materials (EMs) are properly chosen. There are other notable variations in the crystal morphologies and packing of crystals, including key properties such as relatively high density and melting point. These changes occur due to the binding energy, trigger bond energy, trigger bond length, and cohesive energy density of EECCs during cocrystallization. Researchers highly focused on cocrystallization of these four nitramines; earlier reported methods are lacking in selectivity and scalability. When it comes to adoption to industrial scale production of EECCs, it is more difficult. We conducted a thorough literature survey. Also we discussed about a recently developed VPSZ coagglomeration method, which provides a huge opportunity to tune the key properties and performance of existing energetic materials and is easy to scale up to the industrial level.