The switching process in a ferroelectric liquid crystalline side-chain polymer by time-resolved step-scan FT-IR spectroscopy and 2D correlation analysis

Time-resolved Fourier-transform infrared (FT-IR) spectroscopy and two-dimen sional (2D) correlation analysis were used to study the segmental mobility of a ferroelectric liquid-crystalline polymer (FLCP) in the S-c* phase. It has been shown that, under the influence of an electric field, only the mes ogen reorients together with the terminal group attached to it and a fragme nt of the spacer. The remaining part of the spacer and the main chain of th e FLCP do not participate in the reorientation. The estimated relaxation ti mes for selected bands revealed that, according to the theoretical predicti ons, the reorientation rate increases with temperature. This effect is due to the decrease of the reorientational viscosity with temperature. However, the temperature does not effect the mechanism of the reorientation on a mo lecular level. Although the experiment was performed at different voltages we did not observe a field-dependence of the relaxation times. (C) 1998 Els evier Science B.V. All rights reserved.