Temperature-induced composition changes in a critical polymer blend

被引：7

作者：

Enge, W ^{[1
]}

Köhler, W ^{[1
]}

机构：

[1] Univ Bayreuth, Inst Phys, D-95440 Bayreuth, Germany

来源：

CHEMPHYSCHEM | 2004年 / 5卷 / 03期

关键词：

phase transitions; polymers; Soret coefficient; thermal diffusion;

D O I：

10.1002/cphc.200301028

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Approaching critical: Coherent periodic temperature and concentration fluctuations have been excited in a critical polymer blend by means of laser-induced transient gratings (see graphic for results). On the approach to the critical point, the amplitude of the concentration modulation diverges with a mean-field critical exponent far above and Ising-like critical exponent close to the critical temperature. Interestingly, microscopic friction effects cancel out in the Soret coefficient.

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收藏

页码：393 / 395

页数：3

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