Diffusing probe measurements of polystyrene latex particles in polyelectrolyte solutions : Deviations from Stokes-Einstein behavior
Date
2001
Authors
Dunstan, Dave E.
Stokes, Jason
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Macromolecules, 2000; 33 (1):193-198
Statement of Responsibility
Dave E. Dunstan and Jason Stokes
Conference Name
Abstract
The diffusion coefficients of polystyrene latex spheres in both Newtonian and elastic liquids have been measured using dynamic light scattering. The diffusion coefficients of the latex particles measured in glycerol/water (Newtonian) solutions obey Stokes-Einstein behavior over a range of solvent viscosity and temperature. Two apparent diffusion coefficients for the particles are measured in viscoelastic polyacrylamide solutions and are designated Dfast and Dslow. The apparent fast diffusion coefficients measured in the polyacrylamide solutions show an increase to a maximum, above that measured in the solvent water, with increasing polyacrylamide concentration. The apparent fast diffusion coefficient is seen to increase to twice that measured in the water solvent. At higher polyacrylamide concentrations the observed Dfast values decrease below the value obtained in the solvent water. Dfast increases with the scattering vector (q) while Dslow is independent of q.
School/Discipline
School of Chemical Engineering
Dissertation Note
Provenance
Description
© 2000 American Chemical Society