Programmable and adaptive mechanics with liquid crystal polymer networks and elastomers

Abstract

Liquid crystals are the basis of a pervasive technology of the modern era. Yet, as the display market becomes commoditized, researchers in industry, government and academia are increasingly examining liquid crystalline materials in a variety of polymeric forms and discovering their fascinating and useful properties. In this Review, we detail the historical development of liquid crystalline polymeric materials, with emphasis on the thermally and photogenerated macroscale mechanical responses — such as bending, twisting and buckling — and on local-feature development (primarily related to topographical control). Within this framework, we elucidate the benefits of liquid crystallinity and contrast them with other stimuli-induced mechanical responses reported for other materials. We end with an outlook of existing challenges and near-term application opportunities.

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Figure 1: Liquid crystal polymers, polymer networks and elastomers.
Figure 2: Chemical composition, thermomechanical actuation and soft elasticity in liquid crystal elastomers.
Figure 3: Liquid crystal monomers and polymer networks.
Figure 4: Bends, twists and turns in liquid crystal polymer networks.
Figure 5: Reconfigurable topography.
Figure 6: Topography from topological defects.
Figure 7: Communicating through touch.

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Acknowledgements

T.J.W. acknowledges the support of the Air Force Office of Scientific Research and of the Materials and Manufacturing Directorate of the Air Force Research Laboratory.

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White, T., Broer, D. Programmable and adaptive mechanics with liquid crystal polymer networks and elastomers. Nature Mater 14, 1087–1098 (2015). https://doi.org/10.1038/nmat4433

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