One-Dimensional Ion-Conductive Polymer Films:  Alignment and Fixation of Ionic Channels Formed by Self-Organization of Polymerizable Columnar Liquid Crystals

Abstract

We have prepared two types of one-dimensional ion-conductive polymer films containing ion nanochannels that are both perpendicular and parallel to the film surface. These films have been obtained by photopolymerization of aligned columnar liquid crystals of a fan-shaped imidazolium salt having acrylate groups at the periphery. In the columnar structure, the ionic part self-assembles into the inner part of the column. The column is oriented macroscopically in two directions by different methods: orientation perpendicular to the modified surfaces of glass and indium tin oxide with 3-(aminopropyl)triethoxysilane and orientation parallel to a glass surface by mechanical shearing. Ionic conductivities have been measured for the films with columnar orientation vertical and parallel to the surface. Anisotropic ionic conductivities are observed for the oriented films fixed by photopolymerization. The ionic conductivities parallel to the columnar axis are higher than those perpendicular to the columnar axis because the lipophilic part functions as an ion-insulating part. The film with the columns oriented vertically to the surface shows an anisotropy of ionic conductivities higher than that of the film with the columns aligned parallel to the surface.

POSS ionic liquid crystals

“…3,4 Even a small quantity of chiral ionic sources can efficiently induce enantiomeric structures in a bulk sample, and ionic moieties can be assembled to form regularly ordered structures. 5,6 These well-ordered ionic moieties are expected to work as efficient cation carriers and scaffolds for ordering cations. These materials, which comprise closely assembled ionic species, can exhibit interesting optical and magnetic properties.…”

“…7,8 Carmichael et al 9 have synthesized and explored silicon wafer-assisted SILP materials. They created layers with thicknesses between 10 and 21 nm of an ionic LC with [C 18 6 ] on the planar wafer surface and found that the ionic LC formed a mesophase. Inspired by their work, Wasserscheid et al 7 fabricated SILP materials using silicon nanoparticles and used them as supports for preparing mesoporous structures that could act as effective gasphase catalysts.…”

Thermodynamic study of POSS-based ionic liquids with various numbers of ion pairs

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] The increase in molecular weight and the presence of charges often cause an increase in the melting temperature. We have recently reported a polyhedral oligomeric silsesquioxane (POSS)-based room temperature IL that displays a melting temperature below 25 1C.…”

Functional liquid-crystalline polymers and supramolecular liquid crystals

“…Compound 31 forms a Col h phase from 20 to 50°C. 48 Without special treatment, these columnar liquid crystals form a polydomain state. The creation of monodomain states with vertical and parallel alignment can be induced by chemical modification of the substrate of the surface and mechanical shearing, respectively.…”

“…45 Highly cross-linked side-chain-type polymers [45][46][47] and network polymerizable functional molecules 48,49 have been prepared to develop free-standing and mechanically tough functional polymers.…”