Working toward nanotube composites

Pavel Nikolaev, Olga Gorelik and Sivaram Arepalli*

GB Tech/NASA Johnson Space Center, Houston, TX

Carl D. Scott and Bradley S. Files

NASA Johnson Space Center, Houston, TX

Victor G. Hadjiev

Texas Center for Superconductivity, University of Houston, Houston, TX

Abstract

One of the most attractive applications of carbon nanotubes is found in the area of structural materials, using the extraordinarily high strength and modulus to significantly enhance the mechanical properties of today’s composites. In the aerospace industry this is an especially important chance to save weight and this is why NASA has chosen to tackle this difficult application of single wall carbon nanotubes. In this talk we will present recent work by our group as we describe the biggest hurdles, which must be overcome in making nanotube composites a reality. Length calculation of individual nanotubes has been an issue due to the propensity to form bundles. For composite work, aspect ratio of the fibers is a key component. We show here that nanotubes produced in our laser system are as much as tens of microns long. This has been an open question, since it has been shown that some chemically processed and sonicated nanotubes are in the range of hundreds of microns. Also, we will present work on nanotube chemistry, as we attempt to break the bundles into individual tubes while optimizing the interaction between tubes and a matrix polymer. In a joint project with the University of Houston, we present results on in-situ studies of the load transfer in composites using Raman spectroscopy. By using a bending stage we can get information about the stress state of the tubes themselves inside an epoxy matrix.

Keywords: nanotubes, composites, materials, aerospace

Corresponding author and speaker:

Sivaram Arepalli

GBTech/Lockheed Martin

P. O. Box 58561

Mail Stop C61

Houston, TX 77258

Fax: (281) 483-1605

Tel: (281) 483-5910