A revolutionary coating under development for the military could soon combine three capabilities never before seen in coatings technology—the ability to detect scratches and corrosion, to fix such damages on its own, and lastly, to change color to blend in with surroundings. This innovative, nanotechnology-based coating is being produced for a wide range of military vehicles as well as weapons systems.

A research team at the New Jersey Institute of Technology (NJIT) in Newark has recently inked a contract with the U.S. Army to develop these smart coatings. Utilizing them, military vehicles will be able to sense if they are corroded or scratched and self-repair. Tanks, helicopters and military trucks would be able to camouflage themselves on the battlefield, becoming practically invisible. And protected by these futuristic coatings, explosives could become less sensitive and less dangerous for soldiers to carry.

In fact, Army officials say the smart coatings, whose development is being funded by the U.S. Department of Defense, could enable the Army to avoid time-consuming repainting and thus deploy with greater speed, making it an even more formidable force.

But for now, there's plenty of work to be done. "We're just getting started, really," says research team leader Daniel J. Watts, Ph.D., executive director of the York Center for Environmental Engineering and Science and Panasonic Chair in Sustainability at NJIT. Joining his team are researchers from Clemson University in South Carolina. "Our goal is to extend the period of time between initial painting application and the need to strip and repaint," he notes.

Currently, the Army uses paints that are costly and require a lot of labor to apply. And when scratched or corroded, most of the paint calls for repainting, which can cover up damage to metal and other materials. Corrosion-related problems cost about $10 billion a year, with painting and scraping accounting for $2 billion of that total, say Army leaders.

"Currently, up to 20% of army vehicles are out of service due to coatings damage and repainting needs," says Dr. Watts. "Smart coatings can eliminate a lot of those needs," thereby improving Army readiness.

To create an intelligent coating system with unprecedented capabilities, the research team is turning to nanotechnology—the study and manipulation of individual atoms and molecules to make new materials. The researchers will embed the coating with nanomachines—only billionths of a meter in size. These microscopic electromechanical machines will transmit signals to Army personnel, immediately informing them if the coating has sustained damage.

"Existing science says this is possible, that these are achievable goals," says Dr. Watts. "The Beckman Center at the University of Illinois has done research on this showing that monomer capsules embedded in the coatings can repair a scratch. We want to create a new monomer/polymer system that will have multiple-time release capabilities."

Additionally, Dr. Watts hopes to incorporate a nanosensor so the coating system could sense damage and activate the healing process without any human intervention. "We need to think about the ability to detect changes in the body and contour and continuity of the coating. Changes in the integrity of the coating will be picked up by sensors and will trigger responses," he explains. And as for the third goal of the system, he says, "We want the coatings to be able to change colors to match any environment, eliminating the need to repaint vehicles for different theaters of operation."

The research team hopes to complete a prototype coating by 2005, but Dr. Watts says that the first samples will most likely be unable to integrate all three capabilities—detection, self-healing and camouflage. "Will only one prototype do all these things? No, but we may have a few prototypes, each one able to demonstrate one of these capabilities, and then we'll work to combine them," he explains.

And while some may think that the marriage of coatings—a class of products that's considered unsophisticated by consumers—and high technology is an uneasy one, Dr. Watts asserts that it's necessary and appropriate because of the need for military readiness. Says Rep. Rodney Frelinghuysen, New Jersey's senior member of the U.S. House of Representatives Appropriations Committee, who obtained funding for the research, "Smart coating technology will make our armed forces more high-tech and more effective."

Sources: NJIT to Develop Smart Coatings for U.S. Army
Mike Agosta
Coatings World, March 2003
http://www.coatingsworld.com/March032.htm

New Jersey Institute of Technology to Develop Smart Coating for U.S. Army
NJIT Press Release, Nov. 20, 2002
http://www.njit.edu/old/News/Releases/312.html