Spinning carbon nanotubes into future fiber
In a subterranean laboratory in the centre of
Wearing white protective coveralls with a breathing mask, and sealed off behind a plexiglass-walled enclosure, he watches intently as a motorised wheel turning at several centimetres per second drags a fine black thread from the furnace and winds it around a reel.
Afterwards, Juan crawls out from the enclosure, pulls off his mask, takes a few gulps of air and grins.
“What we are dealing with is a single filament, with a diameter of around five microns. So being able to catch it and see it is quite a challenge,” Juan explains over the whirr of machinery.
He jokes: “I think that’s why I got this PhD, because I’m the only one who can see the fibre sometimes.” This experimental rig built at the
One of the principal applications for this new material is in super-strong bullet-proof vests.
The material is already up to several times stronger, tougher and stiffer than fibres currently used to make protective armour.
The UK Ministry of Defence and the
Varied applications
“There are a lot of military applications, uses in speciality products such as sports equipment, in transparent conductive films and in energy. You can go in many different directions,” says Dr Anna Moisala, a member of the team working on the new fibre.
Each fibre contains millions of carbon nanotubes entangled in a network.
Nanotubes are graphite - a common natural form of carbon. In graphite, carbon atoms are bonded in hexagonal structures to form flat layers stacked on top of one another like sheets of paper.
To make nanotubes, scientists essentially take individual graphite layers and fold them over so they join at either edge. This forms cylinders measuring just a few billionths of a metre across.
When pulled along their axes, individual nanotubes have extraordinary strength: “Probably 10 times greater than the strongest fibre we know of,” explains Professor Alan Windle, head of the research group at
“As building blocks, they are very promising indeed,” he says.
Previously, scientists were only able to turn carbon nanotubes into fibres using post-processing techniques. Here, the nanotubes are created and spun into filaments in a single process.
“It is what is called in the trade a ‘disruptive technology’, meaning that it is not an extension of a process that is already used, rather, it is something that is totally ‘left field’,” says Alan Windle.
source: BBC News