Phase chirality and stereo-selective swelling of cholesteric elastomers.

نویسندگان

  • S Courty
  • A R Tajbakhsh
  • E M Terentjev
چکیده

Cholesteric elastomers possess a macroscopic "phase chirality" as the director n rotates in a helical fashion along an optical axis z and can be described by a chiral order parameter alpha. This parameter can be tuned by changing the helix pitch p and the elastic properties of the network at formation. The cholesterics also possess a local nematic order, changing with temperature or during solvent swelling. In this paper, by measuring the power of optical rotation d upsilon /dz , we discover how these two parameters vary as functions of temperature or solvent adsorbed by the network. The main result is a finding of pronounced stereo-selectivity of cholesteric elastomers, demonstrating itself in the retention of the "correct" chirality component of a racemic solvent. It has been possible to quantify the amount of such stereo-separation, and the basic dynamics of the effect.

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عنوان ژورنال:
  • The European physical journal. E, Soft matter

دوره 12 4  شماره 

صفحات  -

تاریخ انتشار 2003