Nitroguanidine is an organic compound with the formula (NH2)2CNNO2. It is a colorless, crystalline solid that melts at 232 °C and decomposes at 250 °C. It is very flammable; but has a low impact sensitivity; however, its detonation velocity is high. It is used as a propellant (air bags), fertilizer, and for other purposes.
Nitroguanidine is produced commercially by a two step process starting with the reaction of calcium cyanamide with ammonium nitrate. Via the intermediacy of biguanidine, this ammonolysis step affords the salt guanidinium nitrate. In the second step, the nitrate salt is treated with sulfuric acid, a process that dehydrates the salt and forms the N-N bond.
Nitroguanidine can also be generated by treatment of urea with ammonium nitrate. Owing to problems of reliability and safety, this process has not been commerciallized despite its attractive economic features.
Nitroguanidine is used as an explosive propellant, notably in triple-base smokeless powder. The nitroguanidine reduces the propellant's flash and flame temperature without sacrificing chamber pressure. These are typically used in large bore guns where barrel erosion and flash are particularly important to avoid.
Nitroguanidine's explosive decomposition is given by the following equation: H4N4CO2 (s) = 2 H2O (g) + 2 N2 (g) + C (s)
The nitrosoylated derivative nitrosoguanidine is often used to mutagenize bacterial cells for biochemical studies.