The cholesteric liquid crystalline (CLC) phase self-organizes into a periodic structure and in the planar orientation, exhibits a selective reflection. These materials are widely considered for applications in optics and photonics, including emerging applications in immersive displays. Polymerization of a small concentration of monomer can stabilize the CLC phase (polymer stabilized CLC, or PSCLC). We have recently been exploring an ion-mediated mechanism to displace the polymer stabilizing network. It is well known that liquid crystal mixtures retain ions such as Na+, NH4+, K+, Mg2+, Ca2+, Zn2+, and Al3+. These ions can negatively impact the performance of liquid crystal devices (response time, image sticking, color staining, and voltage holding ratio). However, these impurities can be leveraged in this mechanism. Accordingly, this presentation reports that the preparation of polymer stabilizing networks with rational incorporation of ion-trapping groups, such as 4-acryloxyterpyridine (TPy-Ac), 4-((6-(Acryloyl)oxy)benzoic-15-crown-5-ether (OBA-15C5), and 4-((6-(Acryloyl)oxy)benzoic-18-crown-6-ether (OBA-18C6). The polar nature of these comonomers can capture transition and alkali metal ions. This presentation will detail the ion-material coupling and the resulting impact on electro-optic performance.
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