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Isotropic-Nematic Transition in Liquid-Crystalline Elastomers

J. V. Selinger·H. G. Jeon·B. R. Ratna
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Abstract

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 crosslinked 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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J. V. Selinger, H. G. Jeon, B. R. Ratna. 2002-09-27. Isotropic-Nematic Transition in Liquid-Crystalline Elastomers. https://doi.org/10.1103/physrevlett.89.225701

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