Effects of Aluminum Additions on the Specific Impulse of Propellants Based on High-Enthalpy Oxidizers Containing NO2 and NF2 Groups

The combustion products ratio and the energy characteristics were evaluated for solid composite propellants containing a mixture of 5,10-bis(trinitromethyl)furazano[3,4-e]di([1,2,4]triazolo)[4,3-a:3',4'-c]pyrazine (I) and 5,10-bis(difluoroamino-dinitromethyl)furazano[3,4-e]di([1,2,4]triazolo)[4,3-a:3',4'-c]pyrazine (II), a binder, and aluminum in various ratios. The introduction of small amounts of Al made it possible to increase the achieved specific impulse Isp by 2.0–2.5 s; the increase was maximum at F/H > 1, but stopped after COF2 started to form in the combustion products at the nozzle exit.