Fabrication of Living Entangled Network Composites Enabled by Mycelium

Abstract Organic polymer‐based composite materials with favorable mechanical performance and functionalities are keystones to various modern industries; however, the environmental pollution stemming from their processing poses a great challenge. In this study, by finding an autonomous phase separating ability of fungal mycelium, a new material fabrication approach is introduced that leverages such biological metabolism‐driven, mycelial growth‐induced phase separation to bypass high‐energy cost and labor‐intensive synthetic methods. The resulting self‐regenerative composites, featuring an entangled network structure of mycelium and assembled organic polymers, exhibit remarkable self‐healing properties, being capable of reversing complete separation and restoring ≈90% of the original strength. These composites further show exceptional mechanical strength, with a high specific strength of 8.15 MPa g.cm −3 , and low water absorption properties (≈33% after 15 days of immersion). This approach spearheads the development of state‐of‐the‐art living composites, which directly utilize bioactive materials to “self‐grow” into materials endowed with exceptional mechanical and functional properties.