Thermal Switching of Selective Reflection for (Polymer Network/Liquid Crystals/Chiral Dopant) Composites

Abstract

The [liquid crystalline polymer network (LCPN) / low molecular weight liquid crystal (LMWLC) / chiral dopant] composite systems were prepared by photo-polymerizing the (photo-polymerizablc liquid crystalline monomer / LMWLC / chiral dopant) mixtures in the homogencously oriented smectic-A (SA) phase. The composite exhibited a drastic reversible change in optical properties between transparent statc and selective reflection one at the SA-chural nematic (N) phase transition. By controlling the fraction of the LCPN and chiral dopant in the composite, file wavelength of reflection band could be cxtended up to the infrared (IR) region. Such a thermo-responsive IR reflection is applicable as a thenno-scnsitive IR shutter.