A second life for wood residuals

木材产品的可回收性大打折扣once synthetic adhesives are used because their presence reduces the varietal purity of wood. An adhesive-free bonding technique, such as friction welding, can be employed instead, but this is energy intensive, and the resulting products suffer from low wet strength³, excluding them from structural application. For the approach proposed by Dong and colleagues, wood is first delignified — that is, chemically treated to remove lignin, exposing the cellulose fibres. Structure-retaining delignification has gained tremendous attention in recent years as it allows the development of cellulose scaffolds that keep the fibre directionality and inherent structure of wood. Moreover, lignin removal increases the cell wall porosity (in the wet state) and facilitates impregnation with organic and inorganic substances, resulting in easier modification and functionalization treatments for improved and novel wood properties. In the wet state, these cellulose scaffolds also show an increased formability, allowing for the design of wooden structures with complex geometries⁴. High-strength cellulose composites and transparent wood are two examples of functional materials fabricated using these new methods^5,6,7,8, with potential applications in the automotive and building sectors.