This title appears in the Scientific Report :
2003
Please use the identifier:
http://dx.doi.org/10.1103/PhysRevLett.91.245501 in citations.
Please use the identifier: http://hdl.handle.net/2128/1621 in citations.
Unusual Thermal Diffusion in Polymer Solutions
Unusual Thermal Diffusion in Polymer Solutions
Thermal diffusion forced Rayleigh scattering results on thermal diffusion of poly(ethylene oxide) (PEO) in ethanol/water mixtures are presented. In water-rich solvent mixtures, PEO is found to migrate towards regions of lower temperature. This is typical for polymer solutions and corresponds to a po...
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Personal Name(s): | de Gans, B.-J. |
---|---|
Wiegand, S. / Luettmer-Strathmann, J. | |
Contributing Institute: |
Weiche Materie; IFF-WM |
Published in: | Physical review letters, 91 (2003) S. 245501-4 |
Imprint: |
College Park, Md.
APS
2003
|
Physical Description: |
245501-4 |
DOI: |
10.1103/PhysRevLett.91.245501 |
Document Type: |
Journal Article |
Research Program: |
Kondensierte Materie |
Series Title: |
Physical Review Letters
91 |
Subject (ZB): | |
Link: |
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Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/1621 in citations.
Thermal diffusion forced Rayleigh scattering results on thermal diffusion of poly(ethylene oxide) (PEO) in ethanol/water mixtures are presented. In water-rich solvent mixtures, PEO is found to migrate towards regions of lower temperature. This is typical for polymer solutions and corresponds to a positive Soret coefficient of PEO. In solvent mixtures with low water content, however, the polymer is found to migrate towards higher temperatures, corresponding to a negative Soret coefficient of PEO in ethanol-rich solutions. To our knowledge, this is the first observed sign change of the Soret coefficient of a polymer in solution. We also present a simple lattice model for the polymer solvent system and calculate Soret coefficients with statistical mechanics methods. The calculated values agree qualitatively with the experimental results. |