Eur. Phys. J. E (2012) 35: 6
https://doi.org/10.1140/epje/i2012-12006-1

Regular Article

Modeling the viscosity and aggregation of suspensions of highly anisotropic nanoparticles

School of Science, Department of Applied Physics, Aalto University, P.O. Box 14100, FI-00076, Aalto, Finland

^* e-mail: Antti.Puisto@aalto.fi

Received: 26 October 2011
Revised: 5 January 2012
Accepted: 11 January 2012
Published online: 26 January 2012

Abstract

The rheology of nanofiber suspensions is studied solving numerically the Population Balance Equations (PBE). To account for the anisotropic nature of nanofibers, a relation is proposed for their hydrodynamic volume. The suspension viscosity is calculated using the computed aggregate size distributions together with the Krieger-Dougherty constitutive equation. The model is fitted to experimental flow curves for Carbon NanoFibers (CNF) and for NanoFibrillated Cellulose (NFC), giving a first estimation of the microscopic anisotropy parameter, and yielding information on the structural properties and rheology of each system.