Syntheses and Physical Properties of Liquid Crystals Containing Ferrocene(XVI) : Phase Transition Behavior of Liquid Crystalline Ferrocene DerivativesContaining Oligosiloxane Spacer

Abstract

Two kinds of monosubstituted ferrocene derivatives with the same mesogen have been prepared. One is containing a disiloxane unit in the spacer, and another is having alkyl spacer. Thermal properties of these compounds have been studied by differential scanning calorimeter (DSC) and polarizing microscope. Furthermore, these compounds were compared from view points of the behavior of phase transitions. The derivative having siloxane spacer has exhibited no liquid crystalline phase, and only crystal - isotropic liquid transition has been observed. On the other hand, the derivative having alkyl spacer has shown a nematic phase. The introduction of the disiloxane unit in the spacer resulted in a drop of transition temperature.