A newly developed form of extremely strong yet readily biodegradable plastic made from common plant proteins is promising to solve the planet’s plastic pollution problem.
Plastic pollution is one of our most pressing environmental crises, with Australia alone generating more than 2.5 million tonnes of plastic waste each year – almost 90 percent of which ends up in our landfills and oceans. There, it degrades our soils and waterways, causing animal deaths and biodiversity loss and releasing greenhouse gases that contribute directly to climate change.
In addition to environmental concerns, microplastics now permeate our own bodies through our food, water and air, and greenhouse gases and other waste substances emitted in plastic production processes are known to have carcinogenic and other deleterious effects.
While interventions such as banning single-use plastics help in the immediate term, until now no alternative material has existed that offers the mechanical performance of conventional plastics.
This is the gap being filled through a partnership between Dr Yi Shen from the University of Sydney’s School of Chemical and Biomolecular Engineering and Australian sustainable packaging producer Honestus Pty Ltd.
Together they are not only addressing plastic pollution at its source but also contributing to a circular economy by developing an innovative process that turns protein-rich agricultural waste into sustainable, high-value packaging materials.
Backed by Dr Shen’s expertise in the natural protein aggregation processes responsible for the development of neurodegenerative diseases including dementia, this partnership is working to exploit this process to convert naturally occurring plant proteins into extremely strong yet readily biodegradable materials capable of replacing conventional plastics in a wide range of applications.
“Our vision is to find a sustainable solution to the grand challenge of plastics pollution,” Dr Shen explains.
“Currently available biodegradable plastics generally require industrial composting processes involving very high temperatures or highly acidic environments. Our protein-based bioplastics, derived from agricultural and food industry protein waste, combine high mechanical performance with natural biodegradability. They readily decompose within weeks under natural conditions in both terrestrial and marine environments, thus mitigating environmental accumulation, avoiding the persistence of microplastics and reducing risks to human and ecosystem health.”
In addition to biodegrading naturally, the fact that the innovative bioplastic film developed by Dr Shen and her team decomposes into its component plant proteins means it cycles those source nutrients back into the ecosystem, representing a circular value-add for the agricultural industry.
The material also integrates ‘smart’ functionality by incorporating a natural pH-responsive substance that changes colour to indicate food spoilage, reducing food waste.
Our vision is to find a sustainable solution to the grand challenge of plastics pollution
The University of Sydney Faculty of Engineering
Dr Shen has a strong track record of translating fundamental research into impactful health and environmental solutions.
Her joint project with Honestus is advancing Australia’s net-zero targets by upcycling our own agricultural by-products into premium sustainable packaging. It’s also building our production capacity in next-generation bioplastics, reducing reliance on imports. Ultimately, the project will repurpose thousands of tonnes of agricultural waste annually and replace millions of dollars’ worth of imported plastic packaging materials. As a result, it will position Australia to capture a significant share of the global sustainable packaging market.
Currently at laboratory prototype stage, the material has already been successfully tested against commercially available benchmarks for mechanical strength, water resistance, vapour permeability and biodegradability.
Next steps include producing market-ready prototypes and validating them under real supply-chain conditions, progressing the project towards a commercialisation strategy prioritising long-term scalability.
Organisations interested in partnering with the University of Sydney on collaborations like this one are encouraged to get in touch to explore how we can assist in scoping, contracting and managing such opportunities.
Learn more about partnership opportunities here.
