Property Improvement of Botanical Concrete with Mycelium

Construction and demolition waste (C&D) generated worldwide is increasing with time. Thus, a sustainable solution is required to recycle them. Botanical concrete (BC) has further been developed as one of the sustainable solutions to solve such challenge. However, it is still associated with incompetent physical properties and high-pressure application problems. Therefore, this study developed an improved botanical concrete composite, pretreated botanical concrete (PBC), which is derived from pretreatment of wood waste with mycelium before mixing with concrete waste and hot-pressing. This study aims to investigate the mechanical, physical, and mechanism of this composite at low pressure application. PBC prepared at 220 ℃ and 30 MPa compaction pressure showed a bending strength of 26 MPa, water absorption of 18%, and thickness swelling of 5%. This is higher than the usual BC and MDF25 (JIS A 5905-2003), allowing its possibility to be used as internal wall panel. Mechanical intrusion porosimetry showed a more compact and denser microstructure in PBC compared to BC, in addition to Fourier-transform infrared spectroscopy results, which revealed S-lignin delignification within pretreated wood by mycelium. These results indicate that mycelium pretreatment can enhance the properties of BC and improve its practicability.