Isotropic-nematic transition in liquid-crystalline elastomers.
نویسندگان
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