Lead Georgia Tech researcher J. Meredith holds a wood- and crab shell-based material that could replace traditional plastic wrap.
ATLANTA - Georgia Institute of Technology researchers have created a material derived from tree fibers and crab shells that has the potential to replace the flexible plastic wrap packaging you use to keep your food fresh.
Researchers derived the new material by spraying alternating layers of chitin and cellulose fibers, sourced from discarded crab shells and wood pulp, respectively, onto a polylactic acid (PLA) base.
“The main benchmark that we compare it to is PET, or polyethylene terephthalate, one of the most common petroleum-based materials in the transparent packaging you see in vending machines and soft drink bottles,” said J. Carson Meredith, a professor in Georgia Tech’s School of Chemical and Biomolecular Engineering.
The research team demonstrated that the new material not only performs the duties of traditional flexible plastic, but that it performs them better.
“Our material showed up to a 67 percent reduction in oxygen permeability over some forms of PET, which means it could, in theory, keep foods fresher longer,” said Meredith.
Cellulose, which comes from plants, is the planet’s most common natural biopolymer, followed next by chitin, which is found in shellfish, insects, and fungi.
Packaging designed to preserve food depends on preventing oxygen from passing through. The new material does this better than plastic because of its crystalline structure.
“It’s difficult for a gas molecule to penetrate a solid crystal, because it has to disrupt the crystal structure,” Meredith said. “Something like PET, on the other hand, has a significant amount of amorphous or non-crystalline content, so there are more paths easier for a small gas molecule to find its way through.”
One problem though: cost. Researchers say a manufacturing process that maximizes economy of scale will have to be developed.
Researchers are also trying to improve the material's ability to block water vapor.
This new material joins the growing list of new, wood-based materials on the rise as of late.
One of these new materials involves the marine tunicate, an exotic sea invertebrate often used in Asian cuisine, which has been combined with wood pulp to form a composite material that's flexible, sustainable, non-toxic, and UV light-reflective. The material could be used in construction, food packaging, biomedical devices, cars, trucks, and boats, say researchers.
French tire maker Michelin has declared that it will begin manufacturing wood-based tires. University of Delaware researchers have developed wood-based sticky tape.
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