Tensile strengths of carbon nanotubes and mechanochemistry of carbon nanotubes
Rodney S. Ruoff*, a, Kevin Ausmana, Oleg Louriea, MinFeng Yua, Henry Rohrsa, Katerina Molonib, Tom Kellyb, Mark Dyerc
aDept of Physics, Washington University CB 1105 One Brookings Drive, St. Louis, MO 63130-4899 USA bDept of Materials Science and Engineering, University of Wisconsin 1509 University Avenue, Madison, WI 53706-1595 c Zyvex LLC 1321 North Plano Road, Suite 200,
Richardson, TX 75081
We have built and used a tool which allows mounting and tensile loading to breaking, of individual carbon nanotubes. We reported on the prototype tests at last years Foresight Conference. Here, we have used a LEO DSM 982 scanning electron microscope (SEM), located in the Materials Science Center at the University of Wisconsin, and have built at Washington University a second generation unit, with some modifications, of the manipulation stage previously built and tested by Zyvex/Ruoff group. The LEO DSM 982 is a particularly accessible, state-of-the-art SEM. After nanotubes have been broken in this device, the two NT sections which result from the original NT breaking, have been investigated with transmission electron microscopy (TEM) at the University of Wisconsin and also on the JEOL FX2000 at Washington University, as a means of determining the inner and outer diameters, and also to examine the nature of the break.
As of July 28, 1999, we have mounted and loaded under tension until broken, over 20 carbon nanotubes, primarily multi-walled carbon nanotubes (MWNTs). It is our goal to report also on the tensile loading and tensile strengths of single-walled carbon nanotubes (SWNTs). It has proven significantly more challenging to "tease" a single SWNT out of the bundles in which they have been present in our samples to date, as compared to pulling out and mounting a single MWNT. We are attempting to achieve better SWNT dispersions in solvents so that they can be dispersed onto the "nanotube sample platform" of the manipulation stage, for easier visualization and pick-and-mount.
We will also report on our continuing research on mechanochemistry, particularly 'kinky chemistry.'
Acknowledgement: support by Zyvex, the NSF, and ONR-DARPA, is acknowledged.
Rodney S. Ruoff
Dept of Physics, Washington University
CB 1105 One Brookings Drive, St. Louis, MO 63130-4899 USA
Phone: 314 935 8746; Fax: 314 935 5258
Email: email@example.com; Web: http://bucky5.wustl.edu