Researchers at RMIT University in Melbourne, Australia, created a sustainable, scalable, and safe-fire-retardant material made of pure mycelium.

Mycelium is the name for the root system of mushrooms. It is an up-and-coming material for insulation and acoustic purposes. The difference with the current material, however, normally mycelium is a composite material, as during its growing period, mycelium feeds on plant waste, like agricultural waste. The new material is made of pure mycelium.

The researchers found a way to grow the pure mycelium in sheets that can be layered and engineered for different uses. These can range from flat panels for the building industry to leather-like material for the fashion industry.

In earlier research, the team already looked into the fire-retardant properties of mycelium. Now, they built upon that to produce a material that can be layered over flammable substrates. By bioengineering the fungi, they were able to make the mycelium structure uniform throughout the material, and keep it paper-thin.

When the material is exposed to radiant heat or fire, the contact layer of the mycelium turns into char, which thermally protects the underlying layers. Unlike many fire-retardant coatings, the mycelium acts as a non-toxic buffer.

Photo: RMIT