Nanocrystalline cellulose extracted from bast fibers: Preparation, characterization, and application

Nanocrystalline cellulose (NCC) have gained great attention owing to their extraordinary properties such as biocompatibility, biodegradability, high crystallinity index (>70%), large surface area (~150 m²/g), high aspect ratio (~70), and high tensile strength (7500 MPa). Bast fibers, with compelling features of easy availability, high fiber length, and high cellulose content, are considered to be competitive raw materials to prepare high quality NCC. Generally, NCC can be obtained by mechanical, chemical, biological or combining methods with the removal of non-cellulosic components from bast fibers. This work summarizes the comprehensive research advancement of NCC extracted from bast fibers. Comparison analysis of geometrical dimensions and microstructure morphologies of NCC are conducted to evaluate the strengths and weaknesses of each preparation method. The characterization of NCC and the application of NCC in many emerging fields are systematically introduced. A detailed discussion of current challenges and future outlook are provided to inspire the relevant researchers.