PB21 Synthesis and Characterization of Dialkylurea with Different Alkyl Groups Showing a Columnar Liquid-Crystalline Property

Abstract

1,3-Dialkylureas with different alkyl groups were prepared and their thermotropic liquid-crystalline behavior was evaluated. In spite of the aliphatic compounds without disc-like molecular shape, these compounds were found to exhibit a columnar phase with two-dimensional hexagonal lattice on in which each column is built up from one-dimensional chains of hydrogen bond. In the urea based materials, we predicted that delocalization of protons along the one-dimensional chains of hydrogen bond is induced, resulting in useful channels for prototropy. Furthermore, we evaluated the electric conductivity of the dialkylurea thin films. The solid films with the columnar structure were found to show an ionic conductivity even under dry conditions.