Sawdust-based biodegradable packaging can nourish aquatic life, researchers discover
23 Mar 2022 --- Researchers at NC State University, US, have developed a new biomaterial that could help solve the worsening problem of plastic pollution. Lokendra Pal and Lucian Lucia, professors in the Department of Forest Biomaterials, have discovered how to convert leftover sawdust powder and agro-residues into styrofoam-like packaging material.
“Our technology represents a significant breakthrough in enhancing [environmental and economic] sustainability while meeting the cost and performance targets needed to make a paradigm shift from plastics-based single-use items, mainly packaging,” the researchers tell PackagingInsights.
“We know this material is not only recyclable and environmentally compatible, but also biodegradable in saltwater. It will simply disappear over time and consequently provide nutrients to aquatic life.”
The researchers say the wood-based material could someday replace the plastics found in many single-use items. With support from the Chancellor’s Innovation Fund, Pal and Lucia are currently conducting pilot trials, in advance of testing and commercialization by potential industry partners.
The researchers say they are currently focused on manufacturing packaging and foodservice products.
Pal and Lucia say current pilot trials include high throughput standard molding processes and the evaluation of commercial viability. “Further, we are looking into developing a continuous process utilizing 3-D printing. Currently, we have two major focus areas – peanut packaging and foodservice items. For the foodservice sector, we are focusing on plates, bowls, cups, utensils, and various other items.”
Harmful styrofoam
Packaging and foodservice products are often made from styrofoam, a popular brand name of polystyrene, which is a petroleum-based plastic.
The researchers say the wood-based material could someday replace the plastics found in many single-use items.The researchers explain that because styrofoam is non-recyclable and non-biodegradable, these products are quickly discarded and make their way into landfills and waterways, where they can take 500 years to decompose.
The researchers say the major challenge was to find a uniform supply of sawdust in terms of particle size, moisture and chemical composition as these all differed depending on the source of wood species. “We were able to mostly overcome these issues through the development of standard processes for pre-screening, drying, and mechanical refining.”
Sawdust benefits
In an effort to address plastic pollution, researchers from around the world have developed biopolymer and fiber-based alternatives. These alternatives, however, require a lot of water, energy and chemicals to produce and therefore cost nearly 10 times as much as the material developed by Pal and Lucia.
Pal and Lucia created a production process that doesn’t require water. Instead, the researchers mechanically sieve, grind and mix sawdust with agro-residues to form a powder. The powder is then combined with a binder before being casted or molded into a packaging item.
Also, because the researchers are utilizing sawdust, the production process is virtually zero-waste and zero-emissions. Sawmills and similar operations usually dispose of their leftover sawdust by burning it. This not only ends the life cycle of a valuable byproduct, but it also produces the greenhouse gas emissions driving climate change. 
Researcher Pal stresses the new material also addresses social equity, reducing the impact of plastic pollution on marginalized communities worldwide.
Additional material benefits
Pal added the material also addresses social equity, reducing the impact of plastic pollution on marginalized communities worldwide. He says that research shows plastic pollution is most highly concentrated along the coasts of low- and middle-income countries, which already have poor waste management systems.
Ultimately, as Pal and Lucia conduct pilot and commercial trials of their material over the next six months, they plan to further test its biodegradability and biocompatibility and to scale production for industrial partners.
The researchers will also explore the use of 3-D printing in the production process, with the goal of eventually creating eco-friendly household items.
By Natalie Schwertheim
