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arXiv · 1801.02596

Liquid crystalline cellulose-based nematogels

Qingkun Liu·Ivan I. Smalyukh
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Abstract

Physical properties of composite materials can be pre-engineered by controlling their structure and composition at the mesoscale. Yet, approaches for achieving this are limited and rarely scalable. We introduce a new breed of self-assembled nematogels formed by an orientationally ordered network of thin cellulose nanofibers infiltrated with a thermotropic nematic fluid. The interplay of orientational ordering within the nematic network and that of the small-molecule liquid crystal around it yields a composite with highly tunable optical properties. By means of combining experimental characterization and modeling, we demonstrate sub-millisecond electric switching of transparency and facile responses of the composite to temperature changes. Finally, we discuss a host of potential technological uses of these self-assembled nematogel composites, ranging from smart and privacy windows to novel flexible displays.

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Qingkun Liu, Ivan I. Smalyukh. 2018-01-08. Liquid crystalline cellulose-based nematogels. https://doi.org/10.1126/sciadv.1700981

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