A group of researchers from Sweden's Chalmers University, for the first time ever, was able to 3D print and copy the unique ultrastructure of wood using a wood-based ink.
The group initially started with an earlier research producing a 3D printing ink through the conversion of wood pulp to a nanocellulose gel.
The researchers were able to interpret and digitize a wood's genetic code which in turn enabled them to be very precise in the arrangement of cellulose nanofibrils; these are the key structural components comprising the structure of wood. Furthermore, this also enabled them to reproduce many of the desirable properties of natural wood such as porosity, toughness and torsional strength.
To further enhance the study, the researchers added hemicellulose, a natural component of plant cells, to the nanocellulose gel, which in turn acts as a glue, giving it added strength, same as that of the natural process of lignification, through which cell walls are built.
The research was headed by Professor Paul Gatenholm and according to him, their technique paved the way for new ways of producing sustainable products, effectively growing them to order. "It means that those products which today are already forest-based can now be 3D printed...and the metals and plastics currently used in 3D printing can be replaced with a renewable, sustainable alternative."
The researchers have already used the technique to develop a prototype for an innovative packaging concept wherein they printed out structures in the form of honeycombs. These have chambers in between printed walls which would serve as chambers for packages, encapsulating them. Given that the chamber itself has a cellulose base, it then has excellent oxygen barrier properties which give way to the possibility of making these honeycomb package containers airtight. Very useful for packaging foodstuffs or pharmaceuticals.
Besides this, the team also considered applications in healthcare products and clothing, But, the team's leader, Gatenholm, has bigger dreams for the project. He stated that he also sees the potential for the technology in space. He believes that this offers the use of the technology in space is the perfect first test bed to develop the technology further. "The source material of plants is fantastically renewable, so the raw materials can be produced on site during longer space travel, or on the moon or on Mars. If you are growing food, there will probably be accessible to both cellulose and hemicellulose," he said.
