Effect of Adding 5-Aminotetrazole to a Modified U.S. ArmyTerephthalic Acid White Smoke Composition

Military visible obscuration compositions (obscurants, smokes) play an important role on today’s battlefield. For many years, the known toxicity or ageing problems of established formulations were commonly accepted since there was a lack of alternatives. Since the U.S. Army stopped producing the AN-M8 hexachloroethane (HC) smoke grenade, the M83 terephthalic acid (TA) smoke grenade has been used in its place. This cool-burning, less toxic, but also low efficiency white smoke formulation cannot compete with HC-based formulations in terms of obscuration performance. In this context, we have explored the use of 5-aminotetrazole (5-AT) as an additive and fuel in the known TA system. Remarkably, it has been found that sugar is not necessarily required in the formulations, which has implications for the future improvement of sublimation-condensation smoke compositions, including coloured smoke compositions. In small-scale tests, it was found that replacing sucrose with 5-AT in the formulations resulted in significantly improved smoke persistence.