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When new explosives are synthesized and developed, handling sensitivity must be measured in a consistent way to dictate safety protocols. Drop-weight impact tests, which represent explosive material sensitivity with the drop height required for a sample to react with 50% probability, are the most common method for understanding and quantifying explosive sensitivity. However, results from impact tests are influenced not only by the explosive material tested but also by the testing conditions and experimental setup. Examples of these testing conditions are the laboratory where the test was performed, the methods for choosing drop height levels and computing sensitivity, and whether grit paper was used to promote the initiation of reactions. We compile a historical data set with over 450 impact test results of the explosive standard pentaerythritol tetranitrate (PETN) from 1959 to 2020. We model the sensitivity of PETN as a function of the test laboratory, the test method, and the use of grit paper and find that all have a significant effect on the measured sensitivity of PETN. We validate the predictions from the fitted model with several new impact tests performed at Los Alamos National Laboratory.

Understanding the factors that affect explosive sensitivity is paramount to the safe handling and development of new explosives molecules. Erythritol tetranitrate (ETN) is an explosive that recently has attracted significant attention in the explosives community because of its ease of synthesis and physical properties. Herein, we report the synthesis of ETN derivatives using azide, nitramine, and nitrate ester functional groups. Impact, spark, and friction sensitivity measurements, computationally calculated explosive properties, and the crystal structure analysis of the ETN derivatives are reported. Mixing explosive functional groups led to changes in the explosive sensitivity, explosive performance as well as physical properties including melting point and physical state at room temperature. Overall, we have demonstrated that combining functional groups can enable the tuning of explosive and physical properties of a molecule. This tunability can potentially aid in the development of new explosives in which characteristics are varied to meet certain specifications.

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Understanding explosive sensitivity is key to the safe handling and development of new explosives. Macro-and microscale studies have concluded that multiple physical and chemical factors affect sensitivity, both intermolecular and intramolecular. Stereoisomers are molecular pairs with the same bond connectivity but differing spatial arrangement of those bonds, and in certain cases can exhibit vastly different chemical and physical properties. Herein we report the synthesis of stereoisomers of erythritol tetranitrate (ETN) and the reported stereoisomers mannitol hexanitrate (MHN) and sorbitol hexanitrate (SHN). Isomers of ETN and MHN had altered physical properties such as melting point, state of matter, and crystal structure. These different physical properties caused changes in the impact sensitivity of the isomers. The melting point of the explosive was determined to be a key factor in the impact sensitivity measurements, altering the physical state of the explosive at room temperature or by potentially facilitating access to the more sensitive liquid state of the explosive.