Thermodynamic and thermal characterization of bishomocubane derivatives as possible binders in composite solid propellants

Abstract

All solid propellant compositions would benefit by substitution of passive binders with high energy density materials (HEDMs). Cage compounds are a new class of potential HEDMs with severely strained molecular structures. This study demonstrates the thermodynamic characterization and energetic properties of two high-nitrogen bishomocubane-based compounds: (i) ditetrazolobishomocubane (DTetzBHC) and (ii) diphenyl-dimethyl-bishomocubane (DPTrizDMBHC). These compounds have higher HoFs and energy densities than traditional hydrocarbon fuels. Ballistic properties such as vacuum specific impulse (Isp) and density vacuum specific impulse (ρIsp) were calculated for these compouds, thus showing promise as possible monomers to replace HTPB as a binder. The detonation properties showed that these oxygen-deficient carbon-rich systems possess potential as explosives. TGA, coupled with IR spectroscopy, revealed that both DPTrizDMBHC and DTetzBHC decompose readily under thermal stress.