Application of spherical ultrafine CuO@AP with core–shell in AP/HTPB composite solid propellant

In order to improve the mechanical and combustion properties of composite solid propellant, the CuO@AP with core–shell structure was prepared by solvent–nonsolvent recrystallization method, and it was applied to AP/HTPB composite solid propellant. The thermal decomposition properties, sensitivity properties and tensile properties of CuO@AP propellant were studied and compared with ultrafine AP propellant, ultrafine spherical AP propellant and the mixture of CuO and AP (CuO/AP) propellant. The results show that the E a of ultrafine spherical AP propellant is 8.16% lower than that of ultrafine AP propellant with the same particle size, and the rate constant increases by 13.64%; the E a of the CuO@AP propellant is 23.63% lower than that of CuO/AP propellant with ultrafine AP of the same particle size, and the rate constant increases by 172.7%. What’s more, the catalytic effect of CuO@AP is obviously better than that of CuO/AP. The impact sensitivity of ultrafine spherical AP propellant is 29.61% lower than that of ultrafine AP propellant with the same particle size, and the ε b is increased by 51.35%. The impact sensitivity of the CuO@AP propellant is 25.38% lower than that of CuO/AP propellant with ultrafine AP of the same particle size, and the ε b is increased by 63.76%. The above shows that the CuO@AP composite particles with core–shell structure have potential application prospects in AP/HTPB propellant.