Application of 3D energetic metal-organic frameworks containing Cu as the combustion catalyst to composite solid propellant

Using traditional metallic combustion catalysts in composite solid propellant (CSP) can lead to sharp energy losses of CSP due to the non-energetic properties of the catalysts. In the current study, the energetic ligands based 3D [Cu(atrz)₃(NO₃)₂]_n metal-organic frameworks (MOF(Cu)) were first used as the combustion catalysts to study their effects on the performance of CSP. It was found that the variation of MOF(Cu) content in the range of 0–5% had no significant effects on the theoretical specific impulse (I_sp) and characteristic velocity (C*) of CSP. MOF(Cu) reduced the high decomposition temperature of AP to 344 °C and the complete decomposition temperature of CSP to 358 °C. It also decreased the thermal decomposition activation energy of CSP from 74.1 kJ mol⁻¹ to 63.3 kJ mol⁻¹. The CSP containing MOF(Cu) exhibits higher burning rates, particular flame structure and lower pressure index, as compared with that with CuO as the catalyst. The mechanical sensitivity test results reveal that MOF(Cu) can reduce the friction sensitivity and impact sensitivity of CSP from 40% and 39.4 cm to 32% and 63.5 cm, respectively. The current study is promising to develop a new kind of energetic combustion catalysts for CSP.