SBIR-STTR Award

Although visual obscurants ("smoke screens") have a long history on the battlefield, use of infrared obscurants (IROs) is comparatively new. IROs are required when the enemy possesses IR based equipment (e.g., thermal sights and heat seeking missiles). Because recent developments have greatly increased the availability of such equipment to numerous military (and non-military groups) around the world, the need for advanced IROs is becoming increasingly important. Although numerous IROs are available, most have limited performance and suffer from environmental and health issues. Among the most promising technologies for future IROs is the carbon nanotube (CNT). In fact, the U.S. Army believes that CNTs may increase IRO effectiveness by approximately a factor of ten. However, currently available CNT production technologies are expensive; and because production cannot be practically implemented in the field, dispersion will prove difficult due to high self-adhesion energies of CNTs. The proposed SBIR program will lead to field deployable production technologies based on traditional low-cost combustion chemistries and equipment. The proposed Phase I will demonstrate direct production of aerosolized CNTs as well as their potential as obscurants. Moreover, the proposed program will lead to low-cost production technologies based on vehicle/aircraft exhaust, resulting in on-demand production of CNT obscurants

The Army seeks significant improvements in the protection of military targets through its use of infrared obscurants (IROs). Specifically, it calls for an order of magnitude improvement on the infrared extinction coefficient, while also minimizing costs. Existing obscurant technologies with organics, metal flakes, and graphite are inherently limited in their performance. The Army recognizes that the unique properties of carbon nanotubes (CNTs) offer a potential solution. Unfortunately, existing CNT production methods, laser, arc discharge, and high pressure CO, are far too expensive to consider for the mass production necessary for obscurants applications. During Phase I research NanoDynamics demonstrated combustion based processes to produce multiwall CNTs as well as significantly higher extinction coefficients as compared to materials such as graphite. The proposed combustion processes can be readily scaled to bulk production and some of these processes can be adapted to run in a continuous manner, directly forming well dispersed CNTs in the field. Phase II research will be focused on the production of optimized CNTs for testing by the Army. Additional work will include investigating scale-up towards bulk production levels and on-demand, well dispersed production technologies that will enable direct production in dedicated field units as well as vehicle exhaust streams.

Keywords:
Carbon Nanotubes, Aerosol Cnts, Infrared Obscurants, Combustion, Diffusion Flames, Vehicle/Aircraft Exhaust, Extinction, Nanotechnology