Tailoring the Mechanical\nProperties of Fungal Mycelium\nMats with Material Extrusion Additive Manufacturing of PHBH and PLA\nBiopolymers

To advance the concept of a circular economy, fungal\nmycelium-based\nmaterials are drawing increased attention as substitutes for nonsustainable\nmaterials, such as petroleum-based and animal-derived products, due\nto their biodegradability, low carbon footprint, and cruelty-free\nnature. Addressing the challenge of mechanical properties in fungal\nmycelium products, this study presents a straightforward approach\nfor reinforcing fungal mycelium mats. This is achieved by using two\nbio-based and biodegradable polymers, poly(3-hydroxybutyrate-<i>co</i>-3-hydroxyhexanoate) (PHBH) and polylactic acid (PLA),\nvia material extrusion additive manufacturing (MEX AM), commonly known\nas 3D printing, to produce fungal mycelium-biopolymer composites.\nBy analyzing the mechanical properties, roughness, and morphology,\nthis study demonstrates significant improvements in ultimate tensile\nstrength with the application of PHBH and even more with PLA, while\nelasticity is reduced. The study also discusses potential improvements\nto enhance the quality of the fungal mycelium-biopolymer composites\nwithout trading off bio-based and biodegradable features, offering\na promising pathway for the development of more durable and sustainable\nfungal mycelium products.