Effects of Dual Oxidizers on the Properties of Composite Solid Rocket Propellants

Abstract

The microstructures and granular distribution of different oxidizers (AP, HMX, CL-20, GUDN, and ADN) were investigated. Several industrial and research types of hydroxyl-terminated polybutadiene (HTPB)-based composite solid rocket propellants containing different dual oxidizers (with a fraction of AP in the reference formulation replaced by HMX, CL-20, GUDN, or ADN), but featuring the same nominal composition, were prepared. The energetic properties and hazardous properties of the corresponding solid propellants were analyzed. The effects of the kind of dual oxidizers on the strand burning rate and pressure exponent of propellants were investigated. Thermal decomposition and the mechanical properties of propellants were also analyzed. It was shown that AP and prilled ADN particles are approximately ball shaped and more uniform than that of the others, while CL-20 is the most irregular one. The application of different oxidizers to composite solid propellants was revealed as feasible, and samples could be cast in vacuum and cured safely. Compositions with ADN or CL-20 filler show higher performance in terms of specific impulse, heat of explosion, burning rate, and density, but are more sensitive to impact and friction. The mechanical properties of mono-oxidizer AP-based composition (reference composition) are superior to those of the others.