This title appears in the Scientific Report :
2003
Please use the identifier:
http://dx.doi.org/10.1063/1.1563601 in citations.
Please use the identifier: http://hdl.handle.net/2128/1620 in citations.
Negative thermodiffusion of polymers and colloids in solvent mixtures
Negative thermodiffusion of polymers and colloids in solvent mixtures
Results on thermodiffusion of poly(ethylene oxide) and colloidal boehmite (gamma-AlOOH) rods in ethanol/water mixtures are presented. Data were obtained using thermal diffusion forced Rayleigh scattering. The sign of the Soret coefficient of the boehmite rods changes from positive to negative with i...
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Personal Name(s): | de Gans, B.-J. |
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Kita, R. / Müller, B. / Wiegand, S. | |
Contributing Institute: |
Weiche Materie; IFF-WM |
Published in: | The @journal of chemical physics, 118 (2003) S. 8073 - 8081 |
Imprint: |
Melville, NY
American Institute of Physics
2003
|
Physical Description: |
8073 - 8081 |
DOI: |
10.1063/1.1563601 |
Document Type: |
Journal Article |
Research Program: |
Kondensierte Materie |
Series Title: |
Journal of Chemical Physics
118 |
Subject (ZB): | |
Link: |
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Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/1620 in citations.
Results on thermodiffusion of poly(ethylene oxide) and colloidal boehmite (gamma-AlOOH) rods in ethanol/water mixtures are presented. Data were obtained using thermal diffusion forced Rayleigh scattering. The sign of the Soret coefficient of the boehmite rods changes from positive to negative with increasing water content, i.e., at sufficiently high water content the colloidal particles move to higher temperatures. The sign of the Soret coefficient of the poly(ethylene oxide) in ethanol/water mixtures is negative, i.e., the poly(ethylene oxide) molecules move to higher temperatures, whereas in pure water the sign is positive. To our knowledge this is the first time that a sign change has been observed for polymers in solution. The analysis of the static light scattering on poly(ethylene oxide) allows the determination of the preferentially solvating solvent. In the investigated concentration range the preferentially solvating solvent is ethanol, in spite of being the poorer solvent for poly(ethylene oxide). (C) 2003 American Institute of Physics. |