Viscoelastic and rheological behavior of concentrated colloidal suspensions
Abstract
Molecular approaches are discussed to the density ({phi}), viscoelastic ({omega}), and rheological ({gamma}) behavior of the viscosity {eta}({phi}, {omega}, {gamma}) of concentrated colloidal suspensions with 0.3 < {phi} < 0.6, where {phi} is the volume fraction, {omega} the applied frequency, and {gamma} the shear rate. These theories are based on the calculation of the pair distribution function P{sub 2}(r; {omega}, {gamma}), where r is the relative position of a pair of colloidal particles. The linear visoelastic behavior {eta}({phi}, {omega}, {gamma} = 0) follows from an equation for P{sub 2}(r, {omega}, {gamma}) derived from the Smoluchowski equation for small {phi}, generalized to large {phi} by introducing the spatial ordering and (cage) diffusion typical for concentrated suspensions. The rheological behavior {eta}({phi}, {omega} = 0, {gamma}) follows from an equation for P{sub 2}(r; {gamma}) of a dense hardsphere fluid derived from the Liouville equation. This leads to a hardsphere viscosity {eta}{sup hs}({phi}, {gamma}) which yields the colloidal one {eta}({phi}, {gamma}) by the scaling relation {eta}({phi}, {gamma})/{eta}{sub 0} = {eta}{sup hs}({phi}, {gamma})/{eta}{sub B}, where {eta}{sub 0} is the solvent viscosity, {eta}{sub B} is the dilute hardsphere (Boltzmann) viscosity, and the {gamma}`s are appropriately scaled. {eta}({phi}, {omega}) and {eta}({phi}, {gamma}) agree well with experiment. Amore »
 Authors:

 Delft Univ. of Technology (Netherlands)
 Rockefeller Univ., New York, NY (United States)
 Publication Date:
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 50770
 Report Number(s):
 CONF940633
Journal ID: IJTHDY; ISSN 0195928X; TRN: 95:0035810005
 DOE Contract Number:
 FG0288ER13847
 Resource Type:
 Journal Article
 Journal Name:
 International Journal of Thermophysics
 Additional Journal Information:
 Journal Volume: 15; Journal Issue: 6; Conference: 12. symposium on thermophysical properties, Boulder, CO (United States), 1924 Jun 1994; Other Information: PBD: Nov 1994
 Country of Publication:
 United States
 Language:
 English
 Subject:
 66 PHYSICS; COLLOIDS; VISCOSITY; DENSITY; RHEOLOGY; BEHAVIOR; BOLTZMANNVLASOV EQUATION; SUSPENSIONS
Citation Formats
Schepper, I.M. de, and Cohen, E G.D. Viscoelastic and rheological behavior of concentrated colloidal suspensions. United States: N. p., 1994.
Web. doi:10.1007/BF01458826.
Schepper, I.M. de, & Cohen, E G.D. Viscoelastic and rheological behavior of concentrated colloidal suspensions. United States. https://doi.org/10.1007/BF01458826
Schepper, I.M. de, and Cohen, E G.D. Tue .
"Viscoelastic and rheological behavior of concentrated colloidal suspensions". United States. https://doi.org/10.1007/BF01458826.
@article{osti_50770,
title = {Viscoelastic and rheological behavior of concentrated colloidal suspensions},
author = {Schepper, I.M. de and Cohen, E G.D.},
abstractNote = {Molecular approaches are discussed to the density ({phi}), viscoelastic ({omega}), and rheological ({gamma}) behavior of the viscosity {eta}({phi}, {omega}, {gamma}) of concentrated colloidal suspensions with 0.3 < {phi} < 0.6, where {phi} is the volume fraction, {omega} the applied frequency, and {gamma} the shear rate. These theories are based on the calculation of the pair distribution function P{sub 2}(r; {omega}, {gamma}), where r is the relative position of a pair of colloidal particles. The linear visoelastic behavior {eta}({phi}, {omega}, {gamma} = 0) follows from an equation for P{sub 2}(r, {omega}, {gamma}) derived from the Smoluchowski equation for small {phi}, generalized to large {phi} by introducing the spatial ordering and (cage) diffusion typical for concentrated suspensions. The rheological behavior {eta}({phi}, {omega} = 0, {gamma}) follows from an equation for P{sub 2}(r; {gamma}) of a dense hardsphere fluid derived from the Liouville equation. This leads to a hardsphere viscosity {eta}{sup hs}({phi}, {gamma}) which yields the colloidal one {eta}({phi}, {gamma}) by the scaling relation {eta}({phi}, {gamma})/{eta}{sub 0} = {eta}{sup hs}({phi}, {gamma})/{eta}{sub B}, where {eta}{sub 0} is the solvent viscosity, {eta}{sub B} is the dilute hardsphere (Boltzmann) viscosity, and the {gamma}`s are appropriately scaled. {eta}({phi}, {omega}) and {eta}({phi}, {gamma}) agree well with experiment. A unified theory for {eta}({phi}, {omega}, {gamma}) is clearly needed and pursued.},
doi = {10.1007/BF01458826},
url = {https://www.osti.gov/biblio/50770},
journal = {International Journal of Thermophysics},
number = 6,
volume = 15,
place = {United States},
year = {1994},
month = {11}
}