MIT team engineered a woody composite which they say it’s as strong as bone and hard as aluminum and it may open up the path for plastic that’s naturally derived.
The strongest part of a tree isn’t in the trunk or its root but in the walls of its cells.
And, a single wood cell wall is made from cellulose or fibers. Cellulose is the most abundant polymer in nature and the main element of plants and algae.
Stronger than Some Types of Bones & Aluminum Alloys?
In each fiber, there are CNCs or reinforcing cellulose nanocrystals. These chains of organic polymers are arranged in almost ideal crystal patterns.
CNCs are more potent and stiffer than Kevlar at the nanoscale. If these crystals can be made into materials in significant fractions, CNCs may be the path to more sustainable, stronger, and plastics which is naturally made.
The MIT team made a composite mostly from cellulose nanocrystals combined with a small amount of synthetic polymer. The organic crystals are 60 to 90 percent of the material and this is the highest CNC amount achieved in a composite until now.
According to the team, this composite based on cellulose is stronger than some bones and aluminum alloys. This material has a microstructure reminiscent of nacre which is the hard inner lining of mollusks.
This New Plastic May Become a Sustainable & Stronger Option for any Traditional Plastic Products
The researchers printed and cast the composite into penny-sized film pieces which they used to test the strength and hardness of the material.
They also machined this composite into a tooth shape to show that it could one day be used for dental implants. It may also be used for any plastic products, but stronger and more sustainable, explain the scientists.
The results of this study are published in the Cellulose journal by Hart and the co-authors.
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