This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).

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Cellulose nanomaterials review: structure, properties and nanocomposites

Cellulose constitutes the most abundant renewable polymer resource available today. As a chemical raw material, it is generally well-known that it has been used in the form of fibers or derivatives for nearly 150 years for a wide spectrum of products and materials in daily life. What has not been known until relatively recently is that when cellulose fibers are subjected to acid hydrolysis, the fibers yield defect-free, rod-like crystalline residues. Cellulose nanocrystals (CNs) have garnered in the materials community a tremendous level of attention that does not appear to be relenting. These biopolymeric assemblies warrant such attention not only because of their unsurpassed quintessential physical and chemical properties (as will become evident in the review) but also because of their inherent renewability and sustainability in addition to their abundance. They have been the subject of a wide array of research efforts as reinforcing agents in nanocomposites due to their low cost, availability, renewability, light weight, nanoscale dimension, and unique morphology. Indeed, CNs are the fundamental constitutive polymeric motifs of macroscopic cellulosic-based fibers whose sheer volume dwarfs any known natural or synthetic biomaterial. Biopolymers such as cellulose and lignin and † North Carolina State University. ‡ Helsinki University of Technology. Dr. Youssef Habibi is a research assistant professor at the Department of Forest Biomaterials at North Carolina State University. He received his Ph.D. in 2004 in organic chemistry from Joseph Fourier University (Grenoble, France) jointly with CERMAV (Centre de Recherche sur les Macromolecules Vegetales) and Cadi Ayyad University (Marrakesh, Morocco). During his Ph.D., he worked on the structural characterization of cell wall polysaccharides and also performed surface chemical modification, mainly TEMPO-mediated oxidation, of crystalline polysaccharides, as well as their nanocrystals. Prior to joining NCSU, he worked as assistant professor at the French Engineering School of Paper, Printing and Biomaterials (PAGORA, Grenoble Institute of Technology, France) on the development of biodegradable nanocomposites based on nanocrystalline polysaccharides. He also spent two years as postdoctoral fellow at the French Institute for Agricultural Research, INRA, where he developed new nanostructured thin films based on cellulose nanowiskers. Dr. Habibi’s research interests include the sustainable production of materials from biomass, development of high performance nanocomposites from lignocellulosic materials, biomass conversion technologies, and the application of novel analytical tools in biomass research. Chem. Rev. 2010, 110, 3479–3500 3479

Cellulose nanocrystals: chemistry, self-assembly, and applications.

Rechargeable lithium-sulfur batteries.

Electrolytes and interphases in Li-ion batteries and beyond.

Cellulose fibrils with widths in the nanometer range are nature-based materials with unique and potentially useful features. Most importantly, these novel nanocelluloses open up the strongly expanding fields of sustainable materials and nanocomposites, as well as medical and life-science devices, to the natural polymer cellulose. The nanodimensions of the structural elements result in a high surface area and hence the powerful interaction of these celluloses with surrounding species, such as water, organic and polymeric compounds, nanoparticles, and living cells. This Review assembles the current knowledge on the isolation of microfibrillated cellulose from wood and its application in nanocomposites; the preparation of nanocrystalline cellulose and its use as a reinforcing agent; and the biofabrication of bacterial nanocellulose, as well as its evaluation as a biomaterial for medical implants.

Nanocelluloses: A New Family of Nature-Based Materials

Review of Recent Research into Cellulosic Whiskers, Their Properties and Their Application in Nanocomposite Field

The lithium/sulfur battery is a promising electrochemical system that has a high theoretical capacity of 1675 mAh g–1, but its discharge mechanism is well-known to be a complex multistep process. As the active material dissolves during cycling, this discharge mechanism was investigated through the electrolyte characterization. Using high-performance liquid chromatography, UV–visible absorption, and electron spin resonance spectroscopies, we investigated the electrolyte composition at different discharge potentials in a TEGDME-based electrolyte. In this study, we propose a possible mechanism for sulfur reduction consisting of three steps. Long polysulfide chains are produced during the first reduction step (2.4–2.2 V vs Li+/Li), such as S82– and S62–, as evidenced by UV and HPLC data. The S3•– radical can also be found in solution because of a disproportionation reaction. S42– is produced during the second reduction step (2.15–2.1 V vs Li+/Li), thus pointing out the gradual decrease of the polysulfide chai...

Lithium/Sulfur Cell Discharge Mechanism: An Original Approach for Intermediate Species Identification

Cellulose nanocrystals reinforced poly(oxyethylene)

New insights into the limiting parameters of the Li/S rechargeable cell

The purpose of this study was to investigate a new way of processing cellulose whiskers reinforced polymer. A stable suspension of tunicin whiskers was obtained in an organic solvent (N,N-dimethylformamide) without a surfactant addition or a chemical surface modification. Both the high value of the dielectric constant of DMF and the medium wettability of tunicin whiskers were supposed to control the stability of the suspension. The nanocomposite materials were prepared by UV cross-linking using an unsaturated polyether as matrix. The resulting films were characterized by SEM, DSC, and mechanical testing in both the linear and nonlinear domains. The processing technique from a N,N-dimethylformamide suspension was found to be successful and led to materials whose properties are similar to those obtained with aqueous medium. It could be a good alternative to broaden the number of possible polymer matrices and to allow the processing of nanocomposite materials from an organic solvent solution instead of using aqueous suspensions.

Fannie Alloin

Papers

Review of Recent Research into Cellulosic Whiskers, Their Properties and Their Application in Nanocomposite Field

Lithium/Sulfur Cell Discharge Mechanism: An Original Approach for Intermediate Species Identification

Cellulose nanocrystals reinforced poly(oxyethylene)

New insights into the limiting parameters of the Li/S rechargeable cell

Preparation of Cellulose Whiskers Reinforced Nanocomposites from an Organic Medium Suspension