Recent Developments in Cellulose Nanomaterial Composites

Cellulose nanomaterials (CNMs) are a class of materials that have recently garnered attention in fields as varied as structural materials, biomaterials, rheology modifiers, construction, paper enhancement, and others. As the principal structural reinforcement of biomass giving wood its mechanical properties, CNM is strong and stiff, but also nontoxic, biodegradable, and sustainable with a very large (Gton yr⁻¹) source. Unfortunately, due to the relatively young nature of the field and inherent incompatibility of CNM with most man-made materials in use today, research has tended to be more basic-science oriented rather than commercially applicable, so there are few CNM-enabled products on the market today. Herein, efforts are presented for preparing and forming cellulose nanomaterial nanocomposites. The focus is on recent efforts attempting to mitigate common impediments to practical commercialization but is also placed in context with traditional efforts. The work is presented in terms of the progress made, and still to be made, on solving the most pressing challenges—getting properties that are competitive with currently used materials, removing organic solvent, solving the inherent incompatibility between CNM and polymers of interest, and incorporation into commonly used industrial processing techniques.