Impact of Straw Substrate Particle Size on the Mechanical Properties of Mycelium Based Composite Materials

This research investigates the application of fungi to the existing linear agricultural and forestry economies to create more circular economic models, reduce CO2 emis-sions, and produce building materials aligning with ac-tion plans of European governments, towards climate neutrality by 2050. In this context, biomaterials in the built environment are considered a critical way forward. The research studies mycelium-based materials for panel boards in buildings. Mycelial structure was proven to be an effective material binder, but there are potential im-provements to product quality and stability in produc-tion. After identifying specific fungi for use as material binder, laboratory tests assessed salient mechanical prop-erties of the mycelium-based composite materials on pelletised vs. chopped/chipped substrate materials. The results show that pelletised substrate materials produce composite materials with isotropic characteristics that are more resistant to compressive loads than composite mate-rials made from chopped substrates. This gives promise that pelletised substrates can improve strength, con-sistency, and reliability of mycelium products while of-fering an industrial solution to biomass waste manage-ment with the production of standardised pellets as an ingredient of mycelium composite materials. The produc-tion process thus has the potential to create a circular economic model for agriculture, forestry, and the built environment, while off-setting biomass incineration.