Crab Shells & Cellulose Offer Promising Plastic Alternative
Brands seeking a sustainable alternative to plastic packaging should take note of a nascent new material made from the two most abundant biopolymers on Earth.
Researchers at Georgia Institute of Technology have used cellulose nanocrystals (from trees) and chitin (from the shells of arthropods like crabs and the cell walls of fungi) to make a flexible, transparent film. When compared with some forms of PET (the plastic widely used for soft drink bottles and packaging), the material reduces oxygen permeability by up to 67% – which means it could improve the shelf-life of foods.
In nature, cellulose and chitin are never found side by side. But when sprayable versions of these materials are laminated together, they work symbiotically to form a dense, thin membrane which is completely compostable. Chitin is a byproduct of shellfish processing, while cellulose can be sourced sustainably from the pulp and paper manufacturing industry.
Each year, up to a third of the food produced for human consumption is wasted before it reaches the dinner table (FAO, 2015). As the population increases, brands will need to find ways to tackle this without contributing to the global problem of plastic pollution. McDonald’s, Starbucks and Pret A Manger are among the big brands pledging to reduce or eliminate single-use plastics from their businesses – see our blog post for more.
Meanwhile, researchers at Singapore University of Technology and Design are developing a cellulose/chitin-based 3D-printed material as an alternative to plastic filament. Read more about this and other cellulose-based plastic alternatives in our report Reframing Wood. For more bioplastic innovations, see Evolving Plastic.