Holographic Grating Study of Mass and Thermal Diffusion of Polystyrene/Toluene Solutions

摘要

The transient grating technique of thermal diffusion forced Rayleigh scattering (TDFRS) has been employed to study translational and thermal diffusion of polystyrene in toluene. Different molar masses and concentrations below or slightly above the overlap concentration c~* have been investigated. The translational diffusion coefficients agree well with results obtained from photon correlation spectroscopy. Small remaining differences can be attributed to sample polydispersity. The molar mass independence of the thermal diffusion coefficient is confirmed, and thermal diffusion and Soret coefficients are compared with data obtained from thermal field flow fractionation and diffusion cell experiments.