# Structure and dynamics of concentrated dispersions of polystyrene latex spheres in glycerol: Static and dynamic x-ray scattering

## Abstract

X-ray photon correlation spectroscopy and small-angle x-ray scattering measurements are applied to characterize the dynamics and structure of concentrated suspensions of charge-stabilized polystyrene latex spheres dispersed in glycerol, for volume fractions between 2.7% and 52%. The static structures of the suspensions show essentially hard-sphere behavior. The short-time dynamics shows good agreement with predictions for the wave-vector-dependent collective diffusion coefficient, which are based on a hard-sphere model [C. W. J. Beenakker and P. Mazur, Physica A 126, 349 (1984)]. However, the intermediate scattering function is found to violate a scaling behavior found previously for a sterically stabilized hard-sphere suspension [P. N. Segre and P. N. Pusey, Phys. Rev. Lett. 77, 771 (1996)]. Our measurements are parametrized in terms of a viscoelastic model for the intermediate scattering function [W. Hess and R. Klein, Adv. Phys. 32, 173 (1983)]. Within this framework, two relaxation modes are predicted to contribute to the decay of the dynamic structure factor, with mode amplitudes depending on both wave vector and volume fraction. Our measurements indicate that, for particle volume fractions smaller than about 0.30, the intermediate scattering function is well described in terms of single-exponential decays, whereas a double-mode structure becomes apparent for more concentrated systems.

- Authors:

- Publication Date:

- Sponsoring Org.:
- (US)

- OSTI Identifier:
- 40205412

- Resource Type:
- Journal Article

- Journal Name:
- Physical Review E

- Additional Journal Information:
- Journal Volume: 62; Journal Issue: 6; Other Information: Othernumber: PLEEE8000062000006008258000001; 063012PRE; PBD: Dec 2000; Journal ID: ISSN 1063-651X

- Publisher:
- The American Physical Society

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; DECAY; DIFFUSION; GLYCEROL; HARD-SPHERE MODEL; LATEX; PHOTONS; POLYSTYRENE; RELAXATION; SCATTERING; SPECTROSCOPY; STRUCTURE FACTORS; VECTORS

### Citation Formats

```
Lumma, D, Lurio, L B, Borthwick, M A, Falus, P, and Mochrie, S G. J.
```*Structure and dynamics of concentrated dispersions of polystyrene latex spheres in glycerol: Static and dynamic x-ray scattering*. United States: N. p., 2000.
Web. doi:10.1103/PhysRevE.62.8258.

```
Lumma, D, Lurio, L B, Borthwick, M A, Falus, P, & Mochrie, S G. J.
```*Structure and dynamics of concentrated dispersions of polystyrene latex spheres in glycerol: Static and dynamic x-ray scattering*. United States. doi:10.1103/PhysRevE.62.8258.

```
Lumma, D, Lurio, L B, Borthwick, M A, Falus, P, and Mochrie, S G. J. Fri .
"Structure and dynamics of concentrated dispersions of polystyrene latex spheres in glycerol: Static and dynamic x-ray scattering". United States. doi:10.1103/PhysRevE.62.8258.
```

```
@article{osti_40205412,
```

title = {Structure and dynamics of concentrated dispersions of polystyrene latex spheres in glycerol: Static and dynamic x-ray scattering},

author = {Lumma, D and Lurio, L B and Borthwick, M A and Falus, P and Mochrie, S G. J.},

abstractNote = {X-ray photon correlation spectroscopy and small-angle x-ray scattering measurements are applied to characterize the dynamics and structure of concentrated suspensions of charge-stabilized polystyrene latex spheres dispersed in glycerol, for volume fractions between 2.7% and 52%. The static structures of the suspensions show essentially hard-sphere behavior. The short-time dynamics shows good agreement with predictions for the wave-vector-dependent collective diffusion coefficient, which are based on a hard-sphere model [C. W. J. Beenakker and P. Mazur, Physica A 126, 349 (1984)]. However, the intermediate scattering function is found to violate a scaling behavior found previously for a sterically stabilized hard-sphere suspension [P. N. Segre and P. N. Pusey, Phys. Rev. Lett. 77, 771 (1996)]. Our measurements are parametrized in terms of a viscoelastic model for the intermediate scattering function [W. Hess and R. Klein, Adv. Phys. 32, 173 (1983)]. Within this framework, two relaxation modes are predicted to contribute to the decay of the dynamic structure factor, with mode amplitudes depending on both wave vector and volume fraction. Our measurements indicate that, for particle volume fractions smaller than about 0.30, the intermediate scattering function is well described in terms of single-exponential decays, whereas a double-mode structure becomes apparent for more concentrated systems.},

doi = {10.1103/PhysRevE.62.8258},

journal = {Physical Review E},

issn = {1063-651X},

number = 6,

volume = 62,

place = {United States},

year = {2000},

month = {12}

}