As the climate warms and historic wildfires ravage our planet, finding new and sustainable ways to protect people and ecosystems from growing fire concerns is crucial. In recent years, mycelium, a root-like structure of fungal strands, has become a tech darling as an ingredient for growing computers, building materials, and leather. More recently, researchers at Australia’s Royal Melbourne Institute of Technology have made promising progress in turning this unique substance into fire-resistant roofing.
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“The best thing about mycelium is that it forms a thermal protective carbon shell when exposed to fire or radiant heat,” RMIT Professor Everson Kandare, an expert in flammability and thermal properties of biomaterials, said in a statement. “The longer and higher the temperature that mycelium charcoal survives at, the better it will be used as a fire retardant material.”
Kandare and his colleagues published their research on mycelium as a flame retardant agent in the journal Degradation and stability of polymers earlier this month. The team was able to create paper-thin sheets of mycelium from edible Basidiomycota mushrooms in containers of sweet, sugary molasses. They then added sodium hydroxide to convert the chitin in the mycelium into chitosan.
When exposed to flames of nearly 1500 degrees Fahrenheit, according to new scientist, the chitosan quickly turned into a protective layer of carbon. “The material caught fire for about a second and then extinguished on its own,” said co-author Tien Huynh. new scientist.
[Related: Fungi spores and knitting combine to make a durable and sustainable building material.]
Many composite siding panels these days contain plastics, which are a human and ecological health nightmare when burned. “Fire retardants containing bromide, iodide, phosphorus and nitrogen are effective, but have adverse health and environmental effects,” Kandare said in the statement. “They raise environmental and health concerns, as carcinogens and neurotoxins that can escape and persist in the environment cause harm to plant and animal life.” Instead, according to the researchers, their mushroom solution only emits water and carbon dioxide.
Of course, plastics are considerably cheaper and easier to produce than mushroom growing, but Huynh added in the statement that organic waste left over from the mushroom growing industry could one day help scale products like this.
“Collaborating with the mushroom industry would eliminate the need for new farms and produce products that meet fire safety needs in a sustainable way,” Huynh said.