Apr 18, 2002
Epoxy hardens up with nanotubes
Scientists have added carbon nanotubes to epoxy to make a composite that's three-and-a-half times as hard as the original epoxy as well as a much better conductor of heat. The University of Pennsylvania researchers reported their work in Applied Physics Letters.
"This is the first published report of enhanced thermal conductivity in a material due to the addition of carbon nanotubes," said Alan "Charlie" Johnson, who led the team. "It's also the first demonstration of simultaneous thermal and mechanical enhancement of a real-world material."
The researchers made composites containing between 1 and 5% single-wall carbon nanotubes by weight in an epoxy matrix. A composite with 1% carbon nanotubes showed a 125% increase in thermal conductivity at room temperature. Meanwhile, a 2 wt% carbon nanotube-epoxy composite increased in indentation hardness by a factor of 3.5.
"These findings add considerably to carbon nanotubes' lustre as possible additives to a variety of materials," said Johnson. "In addition to adhesives such as epoxy, we are looking at nanotube-based greases that might be used to carry heat away from electronic chips."
Johnson also claims that his group has dispersed the nanotubes more evenly in the epoxy than other researchers have.
The University of Pennsylvania says that it is looking for corporate partners and investors to commercialize this patented technology.
About the author
Liz Kalaugher is editor of nanotechweb.org.