Document Type
Article
Publication Date
1986
Abstract
We report static and dynamic light scattering studies of polystyrenes of narrow molecular weight distribution in ethylbenzene (EtPh) and tetrahydrofuran (THF) as solvents. These experiments generate values for z-average radius of gyration, (Rg)₂, weight-average second osmotic virial coefficient, A₂, z-average translational diffusion coefficients, (Dt)z, and hence the diffusion virial coefficients, kD, and the z-average of the inverse frictional radius, 〈Rf-1〉z. The results show that while for a specific molecular weight the 〈Rg〉z values in THF are similar to our experimental values in ethylbenzene and to literature values in benzene or toluene, the A2 values, as well as hydrodynamic radii, are substantially larger for THF. We find that values of "universal ratios" of static and dynamic quantities in ethylbenzene are in good agreement with predictions of renormalization group theory appropriate to the nondraining good-solvent limit, while those for THF are not. We present a more stringent test of universality by plotting the static light scattering data directly in a "scaling" form. Identical polystyrene samples in THF and ethylbenzene are clearly different when analyzed in this way, although they do conform to an empirical universal description for solvents of arbitrary quality. These analyses suggest that in THF polystyrene exists in a more flexible conformation and is closer to the nondraining, good-solvent limit.
Publication Title
Macromolecules
Rights
© 1986 American Chemical Society. Reprinted (adapted) with permission from Macromolecules 19:1, 124-133.
Recommended Citation
K. Venkataswamy, A. M. Jamieson, and R. G. Petschek. Static and dynamic properties of polystyrene in good solvents: ethylbenzene and tetrahydrofuran. Macromolecules 1986 19 (1), 124-133. DOI: 10.1021/ma00155a020