Low-Cost Carbon Nanotubes for Infrared 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.