Researchers from the University of Texas at Dallas have come up with a new fiber four times tougher than spider silk or twenty times more than steel. And what is the key ingredient? ScienCentral News has the answer: carbon nanotubes.
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.
The vast majority of individual termites, belonging to the most highly evolved species, never leave their crowded fortress city, could not see anything if they did, spend their entire existence in the narrow chambers and narrower tunnels of a labyrinth where they were born and where they breathe perpetually the damp, carbon dioxide atmosphere and dread more than anything else being compelled to leave it, even for an instant. The lives of certain human city dwellers who spend their days in air-conditioned offices, pass from them through tunnels of the subway to narrow chambers in some housing development, may seem remotely analogous.
—Joseph Wood Krutch (1893–1970)
The researchers think that this fiber, which is easy to sew, could be integrated into lightweight military uniforms, protecting soldiers and giving them electronic connections. And they did some early experiments. Here is an image of the fiber woven into a fabric (Credit: Univ. of Texas at Dallas).
But as the author points out, there is one major obstacle, price. Try to buy carbon nanotubes online from Carbon Nanotechnologies, Inc. and you'll see prices ranging from $500 to $900 per gram.
You can read the abstract of their full report, "Super-tough carbon-nanotube fibres" published by Nature (Vol. 423, June 12, 2003).
We can come up with a working definition of life, which is what we did for the Viking mission to Mars. We said we could think in terms of a large molecule made up of carbon compounds that can replicate, or make copies of itself, and metabolize food and energy. So that’s the thought: macrocolecule, metabolism, replication.
—Cyril Ponnamperuma (b. 1923)
Source: Ann Marie Cunningham, ScienCentral News, July 24, 2003.