Awards

Japan Explosives Society Paper Award 2022

Research on Aging Degradation and Stabilization of Explosive Materials under Coexistence of Water

　Dr. Yosuke Nishiwaki has been actively studying exothermic reactions of materials used in pyrotechnics and pyrotechnic devices, such as gas generators, when they coexist with water. A mixture of basic copper nitrate (BCN) and guanidine nitrate (GN) is used as a gas generator, and he has identified the decomposition products in the presence of water and clarified the initial mechanism of BCN degradation. The results of this research are expected to elucidate the mechanism of degradation of pyrotechnic compositions containing GN/BCN and to be useful for the development of safe pyrotechnic products. In addition, stabilizers are used in Mg used in pyrotechnics and pyrotechnic devices to prevent degradation. The relationship between the stabilizing effect and the length of the hydrocarbon chain of the surfactant was investigated, and the results revealed that hydrophobic surfactants are effective stabilizers against Mg aging due to ammonium perchlorate and water. The results of this study are expected to be useful for the development of effective stabilizers for pyrotechnic compositions containing Mg. Furthermore, he quantitatively elucidated the relationship between the particle size, specific surface area, and reactivity of the powder with respect to the exothermic reaction of Mg with water. The results of this research will provide necessary information for the evaluation of degradation problems and thermal hazards of Mg, and will greatly contribute to the safe management technology of explosives.
　The results of Dr. Yosuke Nishiwaki's research have deepened our understanding of exothermic reactions of materials used in pyrotechnics and pyrotechnic devices such as gas generators, and the accumulation of kinetic data has contributed greatly to explosion safety engineering. The paper deserves the Best Paper Award from Japan Explosives Society.

Recommended Papers

1. Degradation mechanism of BCN in GN/BCN/water system and the effect of degradation on the thermal behavior of the system, Sci. Technol. Energ. Mater., Vol. 81, No. 3, pp. 76-81 (2020)
2. Stabilization effects of surfactants on aging of Mg powder with ammonium perchlorate in water, Sci. Technol. Energ. Mater., Vol. 82, No. 4, pp. 109-114 (2021)
3. Exothermic reaction of fine and coarse magnesium powders with water, Sci. Technol. Energ. Mater., Vol. 83, No. 1, pp. 20-27 (2022)

Biography