Bamboo-derived nanocellulose microfibres with enhanced wet and dry strength: The role of hemicellulose content

Self-assembled nanocellulose can be used to prepare robust and continuous filaments, and the properties of these filaments are strongly influenced by the chemical composition of nanocellulose, especially the hemicellulose and lignin content. In this work, cellulose nanofibres (CNFs) with controllable hemicellulose content were prepared from raw moso bamboo using alkali treatment and bleaching processes. The subsequent fabrication of CNF-based microfibres was achieved through a two-step coagulation wet spinning process. Notably, the microfibres with reduced hemicellulose content exhibited superior mechanical strength, due to their greater CNF aspect ratio and higher viscosity. To further enhance the mechanical properties of these macrofibres in both dry and wet conditions, organic coagulation and ionic cross-linking processes were employed. After exchanging the monovalent Na + with Cu 2+ , the resulting macrofibres demonstrated a dry-state Young's modulus of 20 GPa and an ultimate strength of 404 MPa. Impressively, the macrofibres retained a superior tensile strength of 58 MPa and Young's modulus of 2 GPa in the wet state. These macrofibres are prepared using simple spinning processes and can flexibly incorporate additional materials, positioning them as ideal candidates for the development of multifunctional composites and various spinning applications.