Abstract
A new liquid crystal of siloxane dimer with an achiral swallow-tail, C11Si3C11, was synthesized and mixed with a chiral material of 4′-(1-butoxy-1-oxopropan-2-yloxy)biphenyl-4-yl 3-bromo-4-[9-(1,1,2,2,3,3,3-hepta-methyltrisiloxanyl)nonyloxy) benzoate, C9SiFLC, for the preparation of binary mixtures for the study. The mesophases under discussion were investigated by means of polarizing microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and electro-optical experiments. The influence of the mixture proportion of C9SiFLC on the occurrence of the chiral smectic C (SmC*) phase was investigated. Finally, the electro-optical properties of the SmC* phase, such as the tilt angle and switching behavior, were also measured.
Acknowledgment
We thank Dr. Jey-Jau Lee for help with the XRD experiments at the National Synchrotron Radiation Research Center (NSRRC, for the beamline BL17A) in Taiwan. Financial support from the National Science Council of Taiwan (ROC) through 98-2221-E-011-004 is gratefully acknowledged.
Notes
a Cr = crystalline phase; SmC = smectic C phase; SmC* = chiral SmC phase; I = isotropic phase, • = phase exists; F = C9SiFLC; D = C11Si3C11.