Current Characterization Methods for Cellulose Nanomaterials
Cellulose nanomaterials constitute a new family of materials comprised of cellulose. They have properties and functionalities distinct from molecular cellulose and wood pulp, which allow a series of novel applications. It is realized that future innovation and technological challenges afforded by these molecules require a proper metrology and measurements ’tool-box’. Such protocols, developed in the broader research community, are critical for the advancement in understanding, process optimization, and utilization of CNMs in materials development. This multi-authors review article establishes detailed best practices, methods, and techniques for characterizing CNM particle morphology, surface chemistry, surface charge, purity, crystallinity, rheological properties, mechanical properties, and toxicity for two distinct forms of CNMs : cellulose nanocrystals and cellulose nanofibrils. It is anticipated that the availability of such a measurements tool-box will facilitate commercialization of cellulose nanomaterials which display a unique combination of characteristics, such as high on-axis stiﬀness, sustainability, scalability, and mechanical reinforcement of a wide variety of materials, leading to their utility across a broad spectrum of high-performance material applications.