Polar nematic liquid crystals in lyotropic solutions of polyglutamates having phenyl alkyl group

Polar-to-nonpolar transition upon increasing the temperature

Abstract

Curiously, polypeptides spontaneously exhibit polar nematic phase in the lyotropic liquid crystal (LC) solutions. In this study, we investigated the second harmonic generation (SHG) response from lyotropic LC solutions of racemic mixtures of poly(gamma-phenyl alkyl glutamate) (nPG, n=1-6) using benzyl alcohol as the solvent. When the carbon number in side chain ester groups was odd (n=1, 3, 5), polar-to-nonpolar transition upon increasing the temperature was observed. On the other hand, only nonpolar nematic phase was observed when the carbon number in side chain ester groups was even (n=2, 4, 6).