TY  - JOUR
A1  - Holländer, Lars
A1  - Kossack, Wilhelm
A1  - Kollosche, Matthias
A1  - Wirges, Werner
A1  - Kremer, Friedrich
A1  - Gerhard, Reimund
T1  - Influence of the remanent polarisation on the liquid crystal alignment in composite films of ferroelectric poly(vinylidene fluoride-trifluoroethylene) and a cyanobiphenyl-based liquid crystal
JF  - Liquid crystals : an international journal of science and technology
N2  - Polymer-dispersed liquid crystals (PDLCs) of ferroelectric poly(vinylidene fluoride-trifluoroethylene) and nematic 4-cyano-4ʹ-n-hexylbiphenyl (6CB) or 4-cyano-4ʹ-n-pentylbiphenyl (5CB) were prepared to study the effect of the remanent polarisation of the polymer on the liquid crystal alignment. We measured the macroscopic alignment of the liquid crystal molecules in the thickness direction by means of Infrared Transition-Moment Orientational Analysis. Electrical poling at 100 V/µm caused an increased order parameter up to 0.15. After subsequent annealing above the nematic-to-isotropic phase-transition temperature, the order parameter was reduced to 0.02. Nevertheless, the order parameter was still higher than for non-poled film indicating a slight orientation in thickness direction. Both values are lower than those expected from model calculations. In agreement with dielectric measurements, we attribute this result to the shielding effect of mobile charge carriers within the liquid crystal inclusions.
KW  - Polymer-dispersed liquid crystal
KW  - ferroelectric polymer
KW  - remanent polarisation
KW  - liquid crystal alignment
Y1  - 2016
U6  - https://doi.org/10.1080/02678292.2016.1185174
SN  - 0267-8292
SN  - 1366-5855
VL  - 43
SP  - 1514
EP  - 1521
PB  - Editions Rodopi BV
CY  - Abingdon
ER  -