Not a new material, but application of topology to existing fibers creates remarkable strength.
A materials scientist has created the world’s toughest fibre using a mechanism based on a slip knot
In material science, toughness is a measure of the amount of energy a material can absorb before breaking. Kevlar, for example, can absorb some 80 Joules per gram before breaking but this is dwarfed by certain natural materials which are much tougher. The silk produced by the giant riverine orb spider, for instance, can absorb around 390 Joules per gram before breaking.
Today, Nicola Pugno at the University of Trento in Italy reveals a remarkably simple trick that dramatically increases the toughness of almost any kind of fibre. Indeed, Pugno says he has used the technique to create the world’s toughest fibre.
The new idea is deceptively simple–it involves no more than tying a slip knot in the fibre, creating a loop of extra fibre that can passes through the knot as it comes under tension.
The mechanism is straightforward. When the fibre is placed in tension, the slip knot begins to tighten and the extra material passes through the knot, dissipating energy through friction.
Of course, the fibre eventually breaks but only after all the material in the loop has passed through the slip knot. [emphasis mine]
By applying this simple trick to a commercial polymer fibre called Endumax, he has increased its toughness from 44 Joules per gram to a remarkable 1070 Joules per gram. That’s the highest value ever recorded. “The proof of concept is experimentally realized making the world’s toughest fibre,” he says.
That’s better even than fibres made from nanotubes which materials scientists are just beginning to make. The strongest of these, made from carbon nanotubes, has a toughness of 970 Joules per gram.
Pugno says his work is just the beginning and that it ought to be possible to use his slip-knot technique to make graphene fibres with a toughness of 100,000 Joules per gram. [emphasis mine]
That was interesting - thank you Ruth!