Morphology and Thermal Behaviour of New Mycelium-Based Composites with Different Types of Substrates

Abstract

The need for new green and sustainable materials has been fostering the development, research and introduction of biodegradable materials from natural and renewable sources. Commercially available biodegradable plastics, while minimizing their environmental impact and exhibiting a set of properties that enable the obtainment of industrial components, usually require complex processing methods, are costly and have limited applicability. A new growth of natural resources based paradigm applied as production process is increasing its relevance as an alternative production process. New materials that combine fungal mycelium with waste materials as coffee grounds or wood waste can be considered as promising to fulfill this new paradigm. This new biomaterial mycelium based composites present controllable and adjustable properties during their growth, being able to grow and penetrate organic substrates, thus forming a tangle of branched fibers and a structure that presents some thermo-mechanical properties similar to the ones of plastics. The aim of the present study was the selection of the optimal inoculation temperature, light, humidity and the best substrate for the fastest and consistent mycelium growth. Four types of mycelium were incubated, namely Pleurotus ostreatus (382), Hypsizygus ulmarius (420), Ganoderma lucidum (560) and Trametes versicolor (620). The influence of the three substrates (coffee grounds, pine waste and general wood waste) on the growth was analyzed both morphologically and thermo-mechanically by means of differential scanning calorimetry (DSC) and X-ray micro computed tomography (microCT).