Turing seafood waste in biodegradable bioplastic
Four designers from The Royal College of Art & Imperial College London developed new manufacturing processes to turn seafood waste into biodegradable, recyclable bioplastics.
The project, called The Shellworks, was developed by Ed Jones, Insiya Jafferjee, Amir Afshar, and Andrew Edwards. It uses chitin, the world’s second most abundant biopolymer. The material is found in crustaceans, insects and fungi. Chitin has to be chemically extracted from the source before it can be turned into the material chitosan, which can then be turned into bioplastic.
The team spent weeks trying to extract chitosan, before they realised they needed the right tools. Therefore, they built a small scale extractor designed to offer complete control over each parameter of the process in order to allow for further experimentation at the polymer level of the material.
Experimenting with the ratios of the base ingredients, the designers can achieve many different material properties. They were able to control stiffness, flexibility and optical clarity, as well as the thickness of the material.
In addition to the extractor, the team also developed three new manufacturing machines tailored to how the material behaves. Dippy, as the first one is called, is a heated dip moulder that takes advantage of the material’s evaporated nature to create 3D forms. The second, called Vaccy, is a steam heated vacuum former that leverages the materials hydromorphic properties to make moulded packaging. Lastly, Sheety is a sheet forming device to create controlled flat sheets, which can be glued together using the liquid form of the bioplastic.
The bioplastic is easily recyclable and can be turned back into the original solution (using the machine Drippy). At the end of the material’s life, it can be used as a natural, non-polluting fertiliser.
The team used the custom machines to prototype potential applications, ranging from anti-bacterial blister packaging and food-safe carrier bags to self-fertilising plant pots.
The designers say, “By designing scalable manufacturing processes, applications tailored to the material, and eco-positive waste streams, we believe we can demonstrate how chitosan bioplastic could become a viable alternative for many of the plastic products we use today.”