Nitro-substituted bishomocubanes: synthesis, characterization, and application as energetic materials

Area of Science:

• Energetic Materials Science
• Computational Chemistry
• Aerospace Propulsion

Background:

• Strained polycyclic compounds offer high energy density for propellant applications.
• Novel synthesis routes are crucial for developing advanced energetic materials.
• Understanding thermodynamic properties is key to evaluating propellant performance.

Purpose of the Study:

• To synthesize and characterize novel high-energy-density strained polycyclic compounds.
• To evaluate the potential of these compounds as standalone fuels or additives in propellant formulations.
• To determine the thermodynamic properties and performance metrics of the synthesized compounds.

Main Methods:

• Synthesis of nitromethyl-1,3-bishomocubane (NMBHC), nitromethylene-1,3-bishomocubane (NMyBHC), and bis(nitromethyl)-1,3-bishomocubane (DNTMBHC) from bishomocubanone.
• Density Functional Theory (DFT) analysis at the B3LYP/6-31G(d) level for geometry optimization and property determination.
• Equilibrium thermodynamics and thermogravimetric analysis (TGA) for performance and evaporation studies.

Main Results:

• NMBHC and NMyBHC demonstrated a density specific impulse improvement of 75 s over standard hydrocarbons.
• Specific impulse with ammonium perchlorate showed a 25-30 s improvement over hydroxy-terminated polybutadiene.
• Thermogravimetric analysis indicated ready evaporation with activation energies of 58.8, 69.2, and 74.5 kJ mol(-1) for NMBHC, NMyBHC, and DNTMBHC, respectively.

Conclusions:

• The synthesized strained polycyclic compounds exhibit high energy density and favorable thermodynamic properties.
• These compounds present a viable alternative to conventional fuels, offering enhanced performance in liquid and solid propellant systems.
• Further research into these novel energetic materials could lead to advancements in aerospace propulsion technology.