Intelligent Machines

Spinning Nanotubes into Fibers

Solutions of carbon nanotubes can be used to make strong, conductive fibers hundreds of meters long.

Apr 20, 2010
To remove iron left over from the manufacturing process, the nanotubes are placed in a chamber above a flask of boiling hydrochloric acid. Evaporated acid precipitates in the upper chamber and drips over the nanotubes and back into the flask below, carrying the iron with it.

Intelligent Machines

Spinning Nanotubes into Fibers

Solutions of carbon nanotubes can be used to make strong, conductive fibers hundreds of meters long.

Apr 20, 2010
To remove iron left over from the manufacturing process, the nanotubes are placed in a chamber above a flask of boiling hydrochloric acid. Evaporated acid precipitates in the upper chamber and drips over the nanotubes and back into the flask below, carrying the iron with it.
Before the acid rinse (right) the nanotubes are fluffy; after (left), they’re densely packed.
Pure nanotubes dissolved in a superacid sit inside a metal cylinder above a beaker of ether. A piston in the cylinder will force the solution through a needle suspended just above the ether.
The nanotube solution solidifies into a fiber as it streams from the needle and into the ether. This spinning process can yield fibers hundreds of meters long.
Graduate student Colin Young places a cardboard frame containing a nanotube-based fiber between the vises of a stretching apparatus.
The sides of the frame are cut and vises pull the nanotube fiber from either end until it breaks. This allows the researchers to determine the fiber’s tensile strength.
An image taken using a scanning electron microscope shows that the nanotubes making up the fiber are all aligned.