Nematic Liquid Crystals with Polar Ordering Formed from Simple Aromatic Polyester

Abstract

In this study, we describe a distinct nematic liquid crystal with polar ordering which is formed from the polar rod-like aromatic copolyester comprising 4-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid. The polarity in the nematic phase appears along the nematic director as determined by second-harmonic generation (SHG). It was found that SHG activity appears in compounds with a high degree of polymerization. This suggests that the strong dipole-dipole interaction between polar rod-like molecules is the origin of the polar structure.