Current Progress in Rheology of Cellulose Nanofibril Suspensions.
Cellulose nanofibrils (CNFs) are produced and commonly used in the form of aqueous suspensions or gels. A number of studies have focused lately on rheological properties of CNF suspensions, which gives insight into properties of such materials and can reflect their behavior during handling. This Review summarizes the recent progress in rheological studies on CNF aqueous suspensions using rotational rheometry. Here, we discuss linear viscoelastic properties, i.e., frequency-dependent storage and loss moduli; shear flow behavior, i.e., apparent viscosity and shear stress as a function of shear rate; local flow characteristics, etc. In this Review, we point out that the rheological behavior of at least two types of CNF suspensions should be distinguished: (i) ones produced using mechanical fibrillation with or without enzymatic pretreatment (no surface chemical modification), which possess highly flocculated structure, and (ii) ones produced involving chemical modification pretreatments, e.g., carboxylation, carboxymethylation, quaternization, or sulfonation, which possess better colloidal stability and do not evidently flocculate.
Department of Chemistry and Chemical Engineering, Division of Applied Chemistry, Chalmers University of Technology , SE-412 96 Gothenburg, Sweden.
Oleksandr
O
Nechyporchuk
Laboratory of Pulp and Paper Science and Graphic Arts (LGP2), Centre national de la recherche scientifique (CNRS), Agefpi, Université Grenoble Alpes , F-38000 Grenoble, France.
Mohamed Naceur
MN
Belgacem
Laboratoire Rhéologie et Procédés (LRP), Centre national de la recherche scientifique (CNRS), Université Grenoble Alpes , F-38000 Grenoble, France.
Frédéric
F
Pignon
D002482:Cellulose / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D012212:Rheology; D013314:Stress, Mechanical; D013535:Suspensions
D013535:Suspensions; D002482:Cellulose