Nanotechnology is Tested in Space

Space Shuttle Atlantis carries the Rensselaer experiment to the ISS

Nanomaterials developed at Rensselaer Polytechnic were taken into space by the Space Shuttle Atlantis earlier this week.

The project, funded by the U.S. Air Force Multi University Research Initiative (MURI), seeks to test the performance of the new nanocomposites in orbit.

Space Shuttle Atlantis will carry the samples to the International Space Station (ISS). The materials will then be mounted to the station’s outer hull in a Passive Experiment Carrier (PEC), and exposed to the rigors of space.

The first new material is a wear-resistant, low-friction nanocomposite, created by mixing nanoscale alumina particles with polytetrafluoroethylene (PTFE), which is known commercially as Teflon. Linda Schadler, Rensselaer Department of Materials Science and Engineering, and her research group introduced different fluorine-coated nanoparticles into conventional PTFE. The small amount of additive caused the wear rate of the PTFE to drop by four orders of magnitude, without affecting the PTFE’s coefficient of friction. The end result is a stronger, more durable PTFE that is almost as nonstick and slippery as untreated PTFE.

The gained benefit, Schadler said, is the difference between PTFE that can survive sliding along a surface for a few kilometers before wearing away, and a nanocomposite that could slide across a surface for more than 100,000 kilometers before wearing away.

“We’re very excited to have this experiment installed in the ISS, and to see how the new material performs in space,” Schadler said. “In a laboratory setting, the wear rate of the material is four orders of magnitude lower than pure PTFE, which means it is considerably more resistant to wear and tear. Just as important, these advances don’t increase the material’s coefficient of friction, which means the increase in durability won’t come at the expense of creating extra friction.”

Affixed to the station, which travels at about 27,700 kph, the nanocomposite sample will be exposed to ultraviolet radiation, and temperatures ranging from -40 degrees to 60 degrees Celsius. The nanocomposite will be mounted on a tribometer, developed by W. Greg Sawyer, Professor of Mechanical and Aerospace Engineering at the University of Florida, which will measure the friction of the material’s surface. A control sample of the material, protected in a vacuum chamber in the PEC, will also be tested. The apparatus will send data in real-time to the ISS laboratory, which in turn will be forwarded to the research team.

The second set of nanomaterials to be launched into space are conductive polymer nanocomposites. During the loading of the tribometers into the PEC for space travel, an opportunity arose to also test the conductivity of carbon nanotube-filled polyamideimide and liquid crystalline polymers as a function of space exposure. The conductive composites, developed by Schadler and former Rensselaer postdoctoral researcher Justin Bult – who is now a researcher at the U.S. Department of Energy National Renewable Energy Laboratory — had to be developed in less than a week.

“It was an exciting week and we weren’t sure if the composites would hold up to the rigorous testing imposed on them to determine if they could even be launched into space,” Schadler said. “It was a thrill when some of them did, and to see the pictures of them mounted in the PEC.”

Publication Date: 23/11/2009

WWW Link: http://www.rpi.edu/

 Subscribe to our Composite News Feed