Scientists develop fully degradable bioplastic from shrimp shells

Researchers at Harvard's Wyss Institute have developed a method to carry out large-scale manufacturing of objects using a fully degradable bioplastic isolated from shrimp shells. 

It means that mascara cases and cosmetics packs can be made from the fully compostable material while exhibiting many of the same properties as those created with synthetic plastics; and without the environmental threat.

Most bioplastics are made from cellulose; however the team’s developed bioplastic from chitosan, a form of chitin, which is responsible for the hardy shells of shrimps and other crustaceans.

The majority of available chitin in the world comes from discarded shrimp shells, and is either thrown away or is already used in cosmetics due to its anti-aging properties.

Sustainable materials

The Wyss Institute team, led by Postdoctoral Fellow Javier Fernandez, Ph.D., and Founding Director Don Ingber, M.D., Ph.D., developed a new way to process the material so that it can be used to fabricate large, 3D objects with complex shapes using traditional casting or injection molding manufacturing techniques.

Their chitosan bioplastic breaks down when returned to the environment within about two weeks, and it releases rich nutrients that efficiently support plant growth.

"There is an urgent need in many industries for sustainable materials that can be mass produced," says Ingber.

"Our scalable manufacturing method shows that chitosan, which is readily available and inexpensive, can serve as a viable bioplastic that could potentially be used instead of conventional plastics for numerous industrial applications."

Modified

"You can make virtually any 3D form with impressive precision from this type of chitosan," adds Fernandez, who molded a series of chess pieces to illustrate the point.

He claims the material can also be modified for use in water and also easily dyed by changing the acidity of the chitosan solution. And the dyes can be collected again and reused when the material is recycled.

This advance validates the potential of using bio-inspired plastics for applications that require large-scale manufacturing, Fernandez explains.

The next challenge is for the team to continue to refine their chitosan fabrication methods so that they can take them out of the laboratory, and move them into a commercial manufacturing facility with an industrial partner.