Functional soft materials from blue phase liquid crystals

Blue phase (BP) liquid crystals are chiral fluids wherein millions of molecules self-assemble into cubic lattices that are on the order of hundred nanometers. As the unit cell sizes of BPs are comparable to the wavelength of light, they exhibit selective Bragg reflections in the visible. The exploitation of the photonic properties of BPs for technological applications is made possible through photopolymerization, a process that renders mechanical robustness and thermal stability. We review here the preparation and characterization of stimuli-responsive, polymeric photonic crystals based on BPs. We highlight recent studies that demonstrate the promise that polymerized BP photonic crystals hold for colorimetric sensing and dynamic light control. We review using Landau-de Gennes simulations for predicting the self-assembly of BPs and the potential for using theory to guide experimental design. Finally, opportunities for using BPs to synthesize new soft materials, such as highly structured polymer meshes, are discussed.

Automated summary

Blue phase (BP) liquid crystals are chiral fluids that exhibit selective Bragg reflections in the visible due to their cubic lattices. Photopolymerization enables the exploitation of the photonic properties of BP for technological applications. This review focuses on the preparation and characterization of stimuli-responsive, polymeric photonic crystals based on BP, highlighting their potential for colorimetric sensing and dynamic light control, as well as the use of simulations and theory in guiding experimental design. Opportunities for synthesizing new soft materials, such as structured polymer meshes, using BP are also discussed.