Dielectric Spectroscopy on Two Concentrations of a Mixture of Low and High Molecular Liquid Crystalline Compounds

Abstract

Dielectric relaxation measurements in the frequency range from 1 Hz to 100 kHz on mixtures of a substituted polyacrylate and 4-n-hexyloxycyanobiphenyl have been carried out. In the mixtures the dielectric absorption properties which can be related to the individual compounds has been detected. The relaxation frequency of the low molecular compound is about 50 to 100 times higher in comparison with the δ-relaxation of the polymer but it exhibits nearly the same high activation energy. From the experimental data it can be concluded that there is a molecular disperse distribution of both compounds in which the dynamics is mainly determined by the excess component, the polymer.

Key Words:

• dielectric relaxation
• liquid crystals
• polymer
• low molecular compound
• mixture
• molecular disperse distribution