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Phase transitions of nematic rubbers

Pierre-Gilles de Gennes·Ko Okumura
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Abstract

Single crystal nematic elastomers undergo a transition from a strongly ordered phase N to an "isotropic" phase I. We show that: (a) samples produced under tension by the Finkelmann procedure are intrinsically anisotropic and should show a small (temperature dependent) birefringence in the high temperature I phase. (b) for the I->Ntransition via cooling there is a spinodal limit but for the N->I transition via heating there is no soft mode at the standard spinodal temperature. (c) the N->I transition is reminiscent of a martensitic transformation: nucleation of the I phase should occur in the form of platelets, making a well defined angle with the director.

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Pierre-Gilles de Gennes, Ko Okumura. 2003-05-15. Phase transitions of nematic rubbers. https://doi.org/10.1209/epl%2Fi2003-00480-8

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