A team of researchers from the U.S. Army Research Laboratory and Washington State University have discovered a new type of energetic material that could have triple the energy content of well-known explosives for the Army of 2050 and beyond.
So, how exactly does one begin the process of tripling the energy content of explosives?
Simple components of air, such as nitrogen and carbon monoxide, can be transformed into high-energy polymeric solids when sufficient pressure and/or temperature is applied.
The energy density of one polymeric form of nitrogen is estimated to be three times that of HMX, one of the most powerful explosives used today, making it desirable for use as a new type of environmentally-friendly energetic material.
However, this polymeric form of nitrogen has only been synthesized at a pressure that is one million times higher than standard atmospheric pressure while simultaneously heated to about seven times room temperature, and does not maintain the polymeric form when these extreme conditions are relaxed.
Carbon monoxide gas, on the other hand, while not as potentially energetic, polymerizes at less extreme conditions, and can be recovered for use at room temperature and pressure.
In an effort to synthesize a higher-energy, nitrogen-rich polymeric solid, but at less extreme conditions than that of the pure form, the team, including ARL's Dr. Iskander Batyrev, performed a joint experimental-theoretical study of chemical mixtures of nitrogen and carbon monoxide under pressure.
Batyrev belongs to a group of ARL researchers led by Dr. Jennifer Ciezak-Jenkins in studies of materials at extreme conditions.
"The WSU team synthesized and characterized a co-polymer form that has a density similar to that of pure polymeric nitrogen, but is formed at less extreme pressures and temperatures," Batyrev said. "While the material is not stable at room conditions, the study revealed important insight into how high-pressure phases can be accessed at reduced pressures, and how stabilization of the material can be accomplished."