Noncrystalline Binder Based Composite Propellant

This study reports on propellants based on cross-linked HTPE binder plasticized with butyl nitroxyethylnitramine (BuNENA) as energetic material and HP 4000D as noncrystalline prepolymer. This binder was conducted with solid loading in the 85%. The results showed an improvement in processability, mechanical properties and burning rate. In addition, its propellant delivers (about 6 seconds) higher performance (specific impulse) than the best existing composite solid rocket propellant. Thermal analyses have performed by (DSC, TGA). The thermal curves have showed a low glass transition temperature ( ) of propellant samples, and there was no sign of binder polymer crystallization at low temperatures (？50°C). Due to its high molecular weight and unsymmetrical or random molecule distributions, the polyether (HP 4000D) has been enhanced the mechanical properties of propellants binder polymer over a large range of temperatures [？50, 50°C]. The propellants described in this paper have presented high volumetric specific impulse (>500？s·gr·cc？1). These factors combined make BuNENA based composite propellant a potentially attractive alternative for a number of missions demanding composite solid propellants. 1. Introduction Much research on composite solid propellants has been performed over the past few decades and much progress has been made, yet many of the fundamental processes are still unknown, and the development of new propellants remains highly empirical. Ways to enhance the performance of solid propellants for rocket and other applications continue to be explored experimentally, including the effects of various additives and the impact of fuel and oxidizer particle sizes on burning behavior. In view of higher energy ( ？s), composite propellants have been extensively used for rocket/missile applications and space missions. A higher specific impulse ( ) of composite propellants is obtained by incorporating a maximum possible amount of solids (oxidizer/metallic fuel) in the binder matrix and substituting the inert materials with energetic ones (energetic plasticizers). Present day applications demand propellants of superior mechanical properties in addition to higher energy content. Due to these contradictory requirements hydroxy-terminated polyether (HTPE) based propellants are plasticized with energetic plasticizers, such as BuNENA, bolster performance and mechanical properties [1]. HTPE with HP 4000D as Prepolymer is capable of taking up solids up to 85% and impart superior mechanical properties without compromising on high storage life, due to its random