Copper acetylide

When dry, copper acetylide is a heat and shock sensitive high explosive, more thermally sensitive than silver acetylide. Copper acetylide is thought to form inside pipes made of copper or an alloy with high copper content, which may result in violent explosion. This was found to be the cause of explosions in acetylene plants, and led to abandonment of copper as a construction material in such plants. Copper catalysts used in petrochemistrycan also possess a degree of risk under certain conditions.

Explosives, Propellants, Detonators - ATF Regulated Explosive Materials