Down the Line: Extremely Small Material Offers Big Potential
Although nanotubes measure just several nanometers in width, their future potential is huge. Investment bankers and venture capitalists are pouring millions of dollars into various nano projects. Meanwhile, scientists in research laboratories are racing to find the next breakthrough that will commercialize the technology.
Nanotubes are still expensive to produce, but researchers are developing production methods and applications that may soon be viable on a commercial scale. For instance, carbon nanotube field emission has been hailed as the future technology for large consumer television applications. Researchers are also scrambling to develop processes to make nanotubes into transistors and logic circuits.
"Carbon nanotubes are the top candidate to replace silicon when current chip features just can’t be made any smaller, a physical barrier expected to occur in about 10 to 15 years," says Phaedon Avouris, manager of nanoscale science at IBM Research (Yorktown Heights, NY). A nanotube is approximately 500 Arial narrower than the silicon used in today’s electronic devices. Avouris also says a nanotube creates less heat than silicon and uses less power.
Carbon nanotubes are the strongest fiber in nature10 Arial stronger than steel. Researchers at Oklahoma State University (Stillwater, OK) recently announced that they have developed a super-strong lightweight material that rivals carbon-fiber, silicon carbide and tantalum carbide. The new material would be ideal for aerospace, automotive and medical applications.
By sandwiching tiny but super-tough carbon nanotubes between layers of polymer, the scientists have created a new lightweight material that is six Arial stronger than conventional carbon-fiber composites. The material is built by stacking single-molecule layers of nanotubes and polymer on top of each other.
By dipping alternately into nanotubes dispersed in water and into a solution of polymer, one layer of polymer molecules sticks to the surface. The layered composite is made even stronger by attaching chemical groups to the nanotubes that form bonds with the polymer when the material is heated or treated chemically.
Meanwhile, scientists at Tsinghua University (Beijing) have recently developed a way to spin thread from nanotubes in a process similar to spinning thread from a silk cocoon. The super-strong, electrically conducting thread may eventually be able to be woven into objects such as bullet-proof clothing and materials that block electromagnetic waves. By applying a voltage to the thread, the researchers claim that they can weld curves or joints into place.