A simple and sustainable method for preparing high-strength, lightweight, dimensional stable, and mildew resistant multifunctional bamboo

Bamboo is a sustainable, functional and rapidly growing natural material with excellent potential in sustainable building and industrial applications. However, as a structural material, bamboo is hindered by its low mechanical strength and poor mildew resistance. In this study, a simple and sustainable process was developed to partially remove lignin and hemicellulose from bamboo through alkaline pretreatment, combined with thermal mechanical compaction, to convert natural bamboo into a lightweight, high-strength, mildew resistant, and durable multifunctional structural material. The results showed that the comprehensive control effectiveness of the alkaline dense bamboo against Aspergillus niger, Penicillium citricola and Trichoderma viridis was 96.2%, the anti-mildew performance was significantly improved. Compared with natural bamboo, the flexural, tensile, and compressive strength of alkaline dense bamboo increased by 6.9 times, 2.5 times, and 4.6 times, respectively, reaching 578 MPa, 410 MPa, and 145 MPa. Compared with some synthetic structural materials with excellent mechanical properties, the alkaline dense bamboo also exhibited superior specific tensile strength and Shore hardness. The multifunctional alkaline dense bamboo prepared in this study provides the possibility for bamboo resources to be widely used in the field of structural engineering.