Isotropic-nematic transition in liquid-crystalline elastomers.

نویسندگان

  • Jonathan V Selinger
  • Hong G Jeon
  • B R Ratna
چکیده

In liquid-crystalline elastomers, the nematic order parameter and the induced strain vary smoothly across the isotropic-nematic transition, without the expected first-order discontinuity. To investigate this smooth variation, we measure the strain as a function of temperature over a range of applied stress, for elastomers cross-linked in the nematic and isotropic phases, and analyze the results using a variation on Landau theory. This analysis shows that the smooth variation arises from quenched disorder in the elastomer, combined with the effects of applied stress and internal stress.

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عنوان ژورنال:
  • Physical review letters

دوره 89 22  شماره 

صفحات  -

تاریخ انتشار 2002