A revolution in military technology. Those words are likely to evoke images of superweapons, or perhaps a new generation of sensors and software. But the next revolution in military technology may center around one of the humblest yet most ubiquitous items of military equipment: the service member’s uniform.
Called second skin, this technology aims at producing fabrics that “breathe,” keeping the wearer comfortable while protecting against chemical and biological agents. On the battlefield, these futuristic military uniforms can make the difference between effectiveness and incapacity, between life and death. Beyond the battlefield, the same technology can save first responders and other emergency workers – as well as serve a host of everyday and industrial purposes.
A Breath of Life
The modern era of chemical and biological warfare agents began a hundred years ago with the use of chlorine and mustard gas during World War I. Commanders soon discovered that the military value of these agents lay not only in their ghastly effects but on the protective measures they forced on defenders.
American troops deployed in the Middle East and Afghanistan face the brutal challenges of wearing full protective gear while fighting in an extreme climate against enemies believed to possess and use chemical warfare agents. Gas masks and other protective gear are clumsy and generally miserable to wear. A soldier encased in full protection against chemical and biological agents soon becomes bathed in sweat, overheated and exhausted. Strenuous activity is misery at best, and soon becomes all but impossible — and fresh air is at a premium. Alertness and mental focus are worn down. In these conditions, soldiers do not fight well.
The solution to this problem is protective gear that “breathes” — that lets air flow through, and especially allows water vapor out — so that perspiration can evaporate, the body’s primary cooling mechanism. Yet the gear must still block chemical and biological agents. And that is where second-skin technology comes into play. But this technology is really just one application of a broader revolution centering on carbon nanotubes.
Carbon Nanotubes Go Big
From the dawn of modern chemistry more than a century ago, carbon has been recognized for its ability to build larger and more complex molecular structures than any other element. Organic chemistry is largely about the things you can do with carbon; it is known for good reason as the building block of life.
Starting around the 1970s, what may be called the architectural potential of carbon grew in attention, and nanogloss dates the first true nanotubes — essentially nano-scale pipes or hoses — to 1991. These pipes, built of linked carbon atoms, can be only a few times larger in diameter than individual atoms, a fineness that earlier engineers could scarcely have dreamed or even conceived of.
Carbon nanotubes have a broad range of potential uses; for example, they can function as fantastically strong nano-ropes. As reported by Engadget, researchers are also working on developing them as transistors more compact than can be achieved with silicon.
But it is their ability to function as pipelines, writes Anne M. Stark of Lawrence Livermore National Laboratory, that has researchers developing fabrics with membranes that incorporate carbon nanotubes. These nanotubes — five thousand times smaller than the diameter of a human hair — provide channels that air and water vapor can pass through, but also block biological agents. Additionally, technology companies with a specialization in aerospace and global security— including Northrop Grumman — are doing significant research in conjunction with academia and government labs. Carbon nanotubes are not restricted to second skins; they are seeing broad usage in other innovations including flexible electronics, advanced manufacturing of aerospace components such as unique optical structures and even the potential development of space elevators.
Even viruses are too bulky to pass through the nanotubes, though air and water vapor pass so freely that the fabric “breathes” better than popular commercial fabrics such as Gore-Tex. Chemical agents are more compact, and could slip through even a nanotube. The solution is to make the nanotubes smart by fitting them with functional groups of molecules that will act as gatekeepers to block the threat. Says Livermore team leader Kuang Jen Wu, the fabric “will be like a smart second skin that responds to the environment.”
The researchers believe that these new, breathable and smart protective fabrics — which may cover any fit of full body clothing plus helmet and gloves, making it resemble present-day combat gear — could be ready for the battlefield within 10 years. But this technology will not stay confined to the battlefield. Like technologies from radio to paramedic services, second skin will soon find civilian applications beyond futuristic military uniforms.
Shields Into Plowshares
The first civilian application for second-skin technology will surely be for hazmat teams and other first responders. Emergency workers also face the threat of deadly agents they must be protected against, combined with the need for strength and alertness that are quickly sapped by conventional protective gear.
Beyond the realm of emergency services, second-skin technology is sure to find a host of other uses, practical and perhaps fashionable as well. Protection against dangerous biological agents will also protect against features of the environment such as hay-fever pollen that can be annoying even if not dangerous. As the technology matures, other health-related capabilities are sure to emerge from second-skin technology.
More broadly, the ability of fabrics to “breathe” is crucial to comfort particularly in warm weather, making this technology applicable to everything we wear, as well as to curtains, tents, and flexible dividers of all sorts, as well as industrial filters — a range of uses along the whole spectrum from utilitarian to fashionable.
Smart breathing adds yet another range of potential uses. By responding to pheromones released by the body, for example, these fabrics might even respond to our moods. Who knows what fashion designers will come up with once they get their hands on smart fabrics?
