Posted on 07/30/2003 10:26:00 AM PDT by LibWhacker
What if you could wear lightweight armor that kept you warm – and let you phone home? Nanotechnologists have come up with a super strong, flexible fiber that can conduct heat and electricity. It could be made into a modern version of chain mail, the heavy metal mesh worn by medieval knights. If woven from the new fiber, modern chain mail could be light as a cotton shirt, but bulletproof.
Molecular Chain Mail
Over hundreds of millions of years of evolution, many animals, plants, and natural materials have developed extraordinary properties. Spider silk, for example, is five times tougher than steel. (Toughness is defined as the measure of the energy needed to break a fiber.) Some nanotechnologists would like to make synthetic yarn with the same toughness as spider silk.
At the NanoTech Institute at the University of Texas at Dallas, a research team headed by Institute director Ray H. Baughman has spun a new lightweight fiber that the scientists say is the toughest known. Their new fiber is four times tougher than spider silk, and 17 times tougher than Kevlar, now used to make bulletproof vests. The team’s key ingredient is tiny carbon nanotubes, miniscule rolled-up sheets of carbon atoms that can be found naturally in soot.
Since carbon nanotubes were discovered in 1991, their enormous promise has intrigued nanotechnologists. Carbon nanotubes are light and flexible, but enormously strong. They also can conduct heat and electricity. Many researchers want to make them into much larger materials with the same useful properties. But because individual carbon nanotubes are very short, they are difficult to align properly into an unbroken yarn, and if they are combined with plastics or other binding materials, they tend to lump together.
Strings of the nanotube fiber.
The new fiber, says chemist John Ferraris, a member of the research team, is “probably one of the first realizations of taking something that has phenomenal properties at the nanoscale, and actually converting it into something that has size that you can do something with.” To make carbon-nanotube fibers, some researchers have tried pulling out threads from bundles of the nanotubes, like drawing silk thread from a cocoon. But the Texas scientists turned to spinning, a method of working with carbon nanotubes originally developed in France.
The Texas group combines carbon nanotubes with water and a plastic. Materials scientist Alan Dalton says the method works because the particular plastic has “an affinity for water and it likes carbon nanotubes. When we assemble the fibers, the polymer latches on to the surface of the nanotubes and forms a gel.” Then the researchers spin the gel—70 times faster than their French counterparts did—to produce long, continuous fibers.
Ferraris explains that this approach allows the researchers to tailor the fibers by adjusting the ratio of carbon nanotubes to plastic, or changing the plastic slightly. The result is fibers with “a wide range of properties that we can actually maximize. We can maximize strength, or toughness, or electrical conductivity or charge-storage capacity” without sacrificing the fiber’s other properties. Ferraris foresees the fiber, which is easy to weave and sew, being woven into “a multifunctional fabric” that could protect wearers as well as provide warmth and telecommunications.
He predicts that antennae and batteries, sensors and electronic connections could be wired into a lightweight military uniform. As so often happens with military wear, the fiber also could be made into fashionable street wear.
At present, however, the major obstacle is the steep price of carbon nanotubes—as high as $15,000 an ounce. The new fiber won’t be widely available until prices drop considerably—and that isn’t likely for another five to ten years.
Dalton, Ferraris, Baughman, and other UTD team members’ work has appeared in Nature, June 12, 2003. Their research is funded by the Defense Advanced Research Projects Agency (DARPA).
High stress , stronger that spandex , less danger for folks pushing the press to test button on date night !
It's gotta future I believe !!!
Stay Safe !
Cool things for boys to play with.
True very true.
That's what I was thinking. "Bulletproof" is a very misleading term if the loose fabric merely doesn't puncture, but gets pushed X inches into your torso by the bullet... though I guess extracting the bullet will be easy for the ER staff ("Nurse, yank on his shirt tail.")
The only exception I can think of is if the fabric instantaneously stiffens when stress is applied, sort of like how your selt belt locks if you jerk forward quickly. If you've ever played with a thick corn starch & water solution, it changes physical properties when pressure is applied... I've always wondered what would happen if you shot that stuff with a bullet. I hypothesize that it would harden quickly enough to shatter into fragments, then the fragments would turn back to liquid.
At any rate, they made the point that that was why bulletproof vests employ seven layers of Kevlar. In other words, three or four layers would "stop" most handgun rounds, but would still permit so much deformation of the material as to be a danger to the person wearing it.
So maybe they plan on layering this stuff, too. Ooops, there goes the "light and flexible" characteristics the article implies you'll have in bulletproof carbon-nanotube t-shirt!
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