Squishy Carbon Nanotube Films

Carbon nanotubes are prized for their strength, but according to a new report, the tiny tubes also possess remarkable springiness (Science 2005, 310, 1307). A group led by Anyuan Cao of the University of Hawaii, Manoa, and Pulickel M. Ajayan of Rensselaer Polytechnic Institute, Troy, N.Y., found that films made of aligned multiwalled carbon nanotubes can be squeezed to less than 15% of their original length and then rebound to their original shape once pressure is removed. Cao and Ajayan's team repeated the compression cycles thousands of times and found the films did not fracture, tear, or collapse, despite the fact that they undergo extreme zigzag buckling. Because of their unique combination of strength and flexibility, the nanotube-based materials could have applications in construction, cushioning, and packaging. Furthermore, the authors note that nanotubes are resistant to chemicals, humidity, and high temperatures, making them superior to many conventional compressible materials.