Synthesis and Physical Properties of Novel T-Shaped Chiral Liquid Crystal Oligomers Possessing Terminal Cyano Groups

Abstract

Recently we found that some chiral compounds possessing molecular biaxiality can stabilize an amorphous blue phase III. We introduced a polar group into the chiral T-shaped molecule in order to couple the molecule with an electric field. We prepared some novel T-shaped chiral compounds possessing a 4-cyanobiphenyl moiety and a mesogenic unit with a chiral center. We investigated their phase transition temperatures and induced helical pitches. We discuss structure-property correlations of the newly designed T-shaped chiral oligomers.

Keywords:

• Liquid crystals
• chirality
• blue phase
• helical pitch

Acknowledgments

This work was partially supported by Research for Promoting Technological Seeds, JST, and a Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science (No. 19550175).

Notes

^a Compounds I and III exhibited N

* to glass transitions on cooling at −10°C and 9°C, respectively.

^b The cooling rate was 0.1°Cmin^{− 1} from the isotropic phase to appearance of the blue phase.