Study of a Concept of Energetic Materials Consisting of a Solid Fuel Matrix Containing Liquid Oxidizer

Abstract

Composite energetic materials such as solid propellants are characterized by a solid fuel, typically a polymeric binder matrix, containing solid oxidizer particles. The energetic performance of solid propellants is inferior to that of liquid or hybrid propellants. The main reason is that the available practical solid oxidizers are less energetic than the available liquid oxidizers. This article presents and studies the novel concept of an energetic material consisting of a solid fuel matrix containing liquid oxidizer units. The oxidizer units may be capsules filled with a liquid oxidizer. The size of the capsules may be similar to that of typical solid oxidizer particles. In this way, one maintains the structural characteristics of a solid material (e.g., solid propellant), yet benefiting from the superior energy of a liquid oxidizer. The study reveals the theoretical energetic performance (specific impulse) of solid propellants containing different liquid oxidizers compared to standard solid propellants consisting of ammonium perchlorate (AP) oxidizer. It is shown that the combination of certain liquid oxidizers such as hydrogen peroxide or nitrogen tetroxide with a hydroxyl-terminated polybutadiene (HTPB) matrix can increase the overall energy by about 20%, implying about 12% increase in the specific impulse. The combustion processes are discussed as well.