You’ve heard of airplanes made from carbon-fiber reinforced (CFRP) plastics. What’s next? Well there’s a sheet of carbon nanotubes—called “buckypaper”—that may create structures for another generation of airplanes. Carbon nanotubes are already being used as a filler in plastics, but only in loadings of 2 or 3 percent. Buckypaper would use significantly higher loadings. The idea of nanotube reinforced composites is not new. Nanotubes are notorious because they clump and tangle, and no one has been able to produce nanotube composites outside of a lab. Researchers hope that may be changing. Rice University in Houston, for example, has been awarded three patents that advance the technology. Lockheed Martin has been awarded another.
Professor Ben Wang and other scientists at Florida State University say they may have the answer. Exposing the tubes to high magnetism lines up the nanotubes in the same direction. Another breakthrough: creating some roughness on the surface so the nanutubes can bond to a matrix material, such as epoxy. The nanotubes in effect take the place of carbon fiber in a composite construction.
You can make extremely thin sheets with the nanotubes—thus use of the word paper. “Bucky” comes from Buckminster Fuller who envisioned shapes now called fullerenes. Stack up hundreds of sheets of the “paper” and you have a composite material that is 10 times lighter but 500 times stronger than a similar sized piece of carbon steel sheet. It’s easy to see why Lockheed Martin is interested. Unlike CFRP, carbon nanotubes conduct electricity like copper or silicon and disperse heat like steel or brass.
FSU plans to spin out a company to make carbon nanotube composites, and says it may even have some commercial products in a year. Considering that buckminsterfullerenes, or “buckyballs” were first discovered by Rice researchers in 1985, the FSU timeline may be a little optimistic. That doesn’t diminish its significance, however.