A research group at the VTT Technical Research Center in Finland has uncovered the secret behind the extraordinary mechanical properties and ultralight weight of certain fungi. It can be used to create new materials to replace plastic by mimicking the complex architectural designs of mushrooms.
The results of this research were published in Science Advances on February 22, 2023.
VTT studies demonstrate for the first time that complex structural, chemical and mechanical features were adapted through evolution by the hoof mushroom (Fomes fomentarius). These features work synergistically to create an entirely new class of high performance materials.
The research findings can be used as a source of inspiration for the bottom-up development of next generation mechanically robust, lightweight and sustainable materials for a variety of applications under laboratory conditions. These include impact-resistant implants, sports equipment, body armor, aircraft exoskeletons, electronics, or windshield surface coatings.
Elucidation of the unique microstructure of bud fungi
Nature provides insight into the design strategies evolved by living organisms to build robust materials. The tinder fungus Fomes is a particularly interesting species for advanced materials applications. It is a common habitat for birch trees, which have an important function of releasing carbon and other nutrients from dead wood. Formes fruiting bodies are cleverly lightweight biological designs that are simple in configuration but efficient in performance. They meet various mechanical and functional needs. For example, protection from insects and fallen branches, reproduction, survival (objectionable texture and taste to the animal), and perennial fruiting body prosperity due to seasonal changes.
A new study from VTT reveals that the fruiting body of Fomes is a functionally graded material with three distinct layers that undergo multiscale hierarchical self-assembly.
“The mycelium network is the major component of all layers. However, in each layer the mycelium exhibits a very distinct microstructure with its own preferred orientation, aspect ratio, density and branch length. The extracellular matrix acts as a reinforcing glue with each layer differing in terms of quantity, polymer content and interconnectivity,” said Pezhman Mohammadi, senior scientist at VTT.
Modifiable structure allows different functions – source of inspiration for new materials
Formes have a very good structure and can be modified to create a wide variety of materials with different properties. Minimal alterations in cell morphology and extracellular macromolecular composition yield diverse materials with different physicochemical characteristics that surpass most natural and artificial materials. Traditional materials typically face property trade-offs (such as increasing weight or density for increased strength or stiffness), but Fomes delivers high performance without these trade-offs.
“Structural design and biochemical principles of the Fomus fungi have been used to fabricate ultra-lightweight technological structures, nanocomposites with enhanced mechanical properties, and novel fabrication of next-generation programmable materials with high-performance functionality. It opens up new possibilities in materials engineering, such as route exploration.In addition, using simple materials to grow materials can help sustain cost, time, mass production, and future methods of manufacturing and consuming materials. It could help us overcome the odds,” explains Pezhman.
Original: VTT Research: Learnings from Mushrooms Could Help Replace Plastics with New High-Performance Ultralight Materials
Than: Finnish VTT Technical Research Center
