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arXiv · 2208.13914

Model for Photoresponsive Nematic Elastomers

André M. Sonnet·Epifanio G. Virga
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Abstract

We study the equilibria of a photoresponsive nematic elastomer ribbon within a continuum theory that builds upon the statistical mechanics model put forward by Corbett and Warner [Phys. Rev. E 78, 061701 (2008)]. We prove that the spontaneous deformation induced by illumination is not monotonically dependent on the intensity $I$. The ribbon's deflection first increases with increasing $I$, as expected, but then decreases and abruptly ceases altogether at a critical value $I_\mathrm{e}$ of $I$. $I_\mathrm{e}$, which is enclosed within a hysteresis loop, marks a first-order shape transition. Finally, we find that there is a critical value of the ribbon's length, depending only on the degree of cross-linking in the material, below which no deflection can be induced in the ribbon, no matter how intense is the light shone on it.

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André M. Sonnet, Epifanio G. Virga. 2022-08-29. Model for Photoresponsive Nematic Elastomers. https://arxiv.org/abs/2208.13914

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