Electric Polarization Frozen by a Polymer Network in Nematic Liquid Crystals

We constructed nematic liquid crystal–polymer network composites by photon-polymerizing monomers in nematic phase under externally applied electric fields. The monomers formed a polymer network which can stabilize not only the director of the liquid crystal but also the electric polarization of the liquid crystal. The composites exhibited different dielectric behaviors depending on whether the monomers were polymerized under DC or AC voltages. When the monomers were polymerized under AC voltages, the formed composite responded to applied electric fields as a dielectric medium. When the monomers were polymerized under DC voltages, the formed composite exhibited a net polarization.