Researchers at RISE and KTH have developed a method in which they produce an extremely rigid and strong bio-based material from nanocellulose. Once the manufacturing process has been scaled up and become commercial, the application potential will be enormous. Both for down-to-earth gadgets and perhaps as self-produced strong, lightweight materials for people who have moved to Mars.
What it is that allows big trees over 100 feet high to stand up are things known as nanofibrils. The fact that nanofibrils, which consists of cellulose, are strong is something that we have known for a long time. And by putting the fibrils together in the right way, it is actually possible to make the mechanical properties even better.
In collaboration with Wallenberg Wood Science Center, researchers at RISE have developed a method of producing fibres of nanocellulose.
Sustainable material that absorbs energy
The most important properties of the new material are mechanical. It is rigid and since most constructions, such as aircraft wings, are based on rigidity, there are many areas of application. But the fibre is also strong, which is important in, for example, a wire that must not break.
"A third important feature is that the material absorbs energy. This means that it could be used in, for example, in bullet-proof vests", says Daniel Söderberg.
The basic material nanocellulose can already be found in one of the sports company Asics models of running shoes, where it replaces plastic material as the shock absorbing foam in the midsole.
Parts of a car to human parts
Other possible uses of the new materials are artificial tendons and ligaments (e.g. the cruciate) for humans and as an ingredient in special composites for car parts and sporting goods.
But as with many other new materials, more research, knowledge and technological development will be required before the manufacturing process can be used commercially.
"Production will get cheaper, but it will take time. I usually compare it to the plastic polyethylene that was produced in the 1930s, but did not become a mass product until the 1970s", says Karl Håkansson.
But the material has the potential to be very useful even before reaching that stage..
"The visions for nanomaterials are often based on them being something very cool. With characteristics such as being light, strong, durable and leading, they should solve many problems. The challenge for everyone working with nanomaterials is to put together the small, small “Lego brick” into something useful", says Daniel Söderberg.
And this is what the researchers behind the process of transforming the nanofibrillar cellulose (NFC) have succeeded with. Manufacturing takes place in a flow cell where two streams of water are quickly directed from each direction on to a third stream of water. The movement of the water causes the fibrils to lie in the same direction. By lowering the pH at the same time, you can get them to attach to each other. The result is a filament in the form of a gel.
"The great advantage with our filament is that it has a combination of mechanical properties that outperforms other bio-based materials", summarises Karl Håkansson.
Manufacturing at Mars?
The future vision of manufacturing on Mars may sound like science fiction, but there are actually already people who plan to move to the planet. The Dutch project Mars One wants to send 100 selected people to the planet in 2024 and 2026. SpaceX has similar plans, as do Nasa and the space agencies in Russia and China.
And If people manage to settle on Mars, they must of course have something to eat: that can be grown in greenhouses in the capsule they live in or outdoors if it is possible (and edible).
"And in the plants there will be nanocellulose that it is possible to manufacture things from. This avoids very expensive imports from the Earth", says Daniel Söderberg.