3D Printing

3D-printed objects created entirely from wood cellulose

3D-printed objects created ent...
The same material that gives trees their structural integrity can now be used to 3D print tiny chairs, electrical circuits, and other objects
The same material that gives trees their structural integrity can now be used to 3D print tiny chairs, electrical circuits, and other objects
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A circuit in the shape of a tree, in which the conductive element is produced with a 3D-bioprinted nanocellulose ink that contains carbon nanotubes
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A circuit in the shape of a tree, in which the conductive element is produced with a 3D-bioprinted nanocellulose ink that contains carbon nanotubes
The black stuff is conductive nanocellulose gel, which contains carbon nanotubes, while the clear lump next to it is non-conductive nanocellulose gel
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The black stuff is conductive nanocellulose gel, which contains carbon nanotubes, while the clear lump next to it is non-conductive nanocellulose gel
Lead researcher Paul Gatenholm stands beside the 3D bioprinter used to print the nanocellulose structures
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Lead researcher Paul Gatenholm stands beside the 3D bioprinter used to print the nanocellulose structures
The same material that gives trees their structural integrity can now be used to 3D print tiny chairs, electrical circuits, and other objects
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The same material that gives trees their structural integrity can now be used to 3D print tiny chairs, electrical circuits, and other objects
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The 3D printing revolution brings with it a harmful side effect: the special inks that it uses are derived (for the most part) from environmentally-unfriendly processes involving fossil fuels and toxic byproducts. But now scientists at Chalmers University of Technology have succeeded in using cellulose – the most abundant organic compound on the planet – in a 3D printer. They were also able to create electrically-conductive materials by adding carbon nanotubes.

To be specific, the researchers used nanocellulose obtained from wood pulp. This is the stuff that forms the scaffolding that makes trees able to stand tall. It's available in massive quantities, plus it's biodegradable, incredibly strong, renewable, and reusing it keeps the carbon dioxide it contains from entering the atmosphere.

Normally, 3D printing uses a heated liquid form of plastic or metal that hardens and solidifies as it cools and dries. But cellulose doesn't melt when you heat it, so it's not previously been considered a suitable material.

A circuit in the shape of a tree, in which the conductive element is produced with a 3D-bioprinted nanocellulose ink that contains carbon nanotubes
A circuit in the shape of a tree, in which the conductive element is produced with a 3D-bioprinted nanocellulose ink that contains carbon nanotubes

The researchers mixed the cellulose in a hydrogel of 95-99 percent water, which allowed it to go into a 3D bioprinter, and in some instances with carbon nanotubes so that it could conduct electricity. The very high water content of the resultant printer gel meant that the drying process had to be carefully controlled so as not to lose the object's 3D structure. The scientists found that they could also allow the structure to collapse into a thin film (like a circuit).

"Potential applications range from sensors integrated with packaging, to textiles that convert body heat to electricity, and wound dressings that can communicate with healthcare workers," says lead researcher Paul Gatenholm. "Our research group now moves on with the next challenge: to use all wood biopolymers besides cellulose."

The researchers presented their findings at the New Materials From Trees conference in Stockholm earlier this week.

Source: Chalmers University of Technology

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2 comments
Bob Flint
Print & drying time, layer thickness, resolution, cost, etc...
JebaQpt
tiny small cellulose chair from 3d print. How must cost it would be? https://www.youtube.com/watch?v=ztCJUUtNcAc