A material made of a fungus paste injected into a knitted textile ‘frame’ may some day become a common and versatile construction product, scientists hope.
Dubbed ‘mycocrete’, the prototype composite is said to have excellent thermal and acoustic properties, making it suitable for a range of applications. It could be used in insulation or sound-proofing, for instance, replacing foams, timber, and plastics within building interiors.
Furthermore, the material can be grown at temperatures around 25C in a carbon neutral process, using agricultural by-products as a bulk aggregate and nutrition source for the fungus.
Dr Jane Scott, from Newcastle University, said: “Our ambition is to transform the look, feel and well-being of architectural spaces using mycelium [the root network] in combination with bio-based materials such as wool, sawdust and cellulose.”
Scott’s team, which includes designers and engineers, presented their latest research in a paper published in Frontiers in Bioengineering & Biotechnology earlier this month.
They form part of the Living Textiles Research Group, at the Hub for Biotechnology in the Built Environment – itself a joint venture between Newcastle and Northumbria universities.
Mycocrete is said to be a stronger and more versatile composite than previous experiments with bio-materials, and that’s down to the knitted frame – or ‘formwork’ – that not only enhances the structural form, but also enables the organic element to ‘breathe’.
Root of the problem
To make composites using mycelium, the scientists mix spores with grains they can feed on and material that they can grow on. This mixture is packed into a mould and placed in a dark, humid, and warm environment so that the mycelium can grow, binding the substrate tightly together.
Once it’s reached the right density, but before it starts to produce the fruiting bodies we call mushrooms, it is dried out. According to the scientists, this process could provide a cheap, sustainable replacement for foam, timber, and plastic.
However, mycelium needs oxygen to grow, which constrains the size and shape of conventional rigid moulds and limits current applications.
That’s where the knitted textiles come in: oxygen-permeable moulds that could change from flexible to stiff with the growth of the mycelium.
“Knitting is an incredibly versatile 3D manufacturing system,” Scott said. “It is lightweight, flexible, and formable. The major advantage of knitting technology compared to other textile processes is the ability to knit 3D structures and forms with no seams and no waste.”
The team built a prototype structure they called BioKnit to offer proof of their concept. The complex, free-standing dome was built – grown, should we say? – in a single piece, without joins that might prove weak points.
Scott added: “The mechanical performance of the mycocrete used in combination with permanent knitted formwork is a significant result, and a step towards the use of mycelium and textile bio-hybrids within construction.”
Main image: BioKnit dome created to demonstrate the mycocrete composite material, courtesy of Newcastle University.
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