Biodegradable plastic developed using wood byproductsSiobhan Treacy | March 30, 2021
Researchers from the University of Wisconsin, University of Maryland and Yale University created a way to turn wood pulp into biodegradable plastic.
The production of renewable and biodegradable plastics is often expensive and requires toxic chemicals. Even if these plastics can be produced, their mechanical strength and water stability are often insufficient. The team’s new method uses wood byproducts to create more durable and sustainable bioplastics.
The new plastic is made by deconstructing the porous matrix of natural wood and creating a slurry. The resulting material has high mechanical strength, stability when holding liquids and UV light resistance. It can be recycled and safely biodegraded in a natural environment, offering a lower life cycle environmental impact compared to petroleum-based plastics and other biodegradable plastics. The new manufacturing process is straightforward and simple.
To create the slurry mixture, wood powder, a processing residue typically discarded as waste, is deconstructed with biodegradable and recyclable deep eutectic solvent (DES). The resulting product features a nanoscale entanglement and hydrogen between bonding with regenerated lignin and cellulose micro and nanofibrils. The new material has a high solid content and high viscosity that can be cast and rolled out without breaking.
The team conducted a comprehensive life cycle assessment to test the environmental impact of bioplastic versus common plastics. Sheets of bioplastic buried in soil fractured after two weeks and degraded completely after three months. Bioplastic can also be broken down into a slurry with mechanical stirring, which allows it to be recycled and reused.
The new plastic could be used in a variety of ways. It could be molded into plastic bags and packaging, one of the biggest contributors to single-use plastic waste. It also has potential in the automobile industry.
The team is looking at the potential impact that scaling up the production of their plastic could have on forests. Currently, the researchers are using wood byproducts in manufacturing, but large-scale production would require massive amounts of wood. They have started working with forest ecologists to create forest simulation models which would help them link forest growth cycles with the manufacturing process.
A paper on this new plastic was published in Nature Sustainability.