Amphotropic liquid crystal polyacetylene derivative bearing pyrimidine type mesogen

Abstract

An amphotropic liquid crystal polyacetylene derivative with pyrimidine–type two-ringed mesogenic core, exhibiting both thermotropic and lyotropic liquid crystallinity, was synthesized in this study. The polyacetylene derivative showed a lyotropic liquid crystal in d-limonene. The cis configuration of the main chain was confirmed via ¹H NMR. Heat treatment induced cis–trans isomerization of the as-prepared polymer. Gas-phase iodine doping of the polymer initiated a chemical interaction between the polyene and iodine, acting as an electron acceptor, generating charge carriers (radical cations, solitons) detected with the electron spin resonance spectroscopy. Moreover, gas phase doping of the polymer induced cis–trans isomerization.

Keywords:

• Amphotropic liquid crystal
• d-limonene
• electrodopant
• electron spin resonance
• mono-substituted polyacetylene

Acknowledgments

We would like to thank the Open Facility, Research Facility Center for Science and Technology, University of Tsukuba for NMR and DSC measurements, as well as the Glass Workshop of the University of Tsukuba. P–009 as a mesogenic core material was kindly gifted by Midori Kagaku Co. (Midori Chemical Industry, Tokyo, Japan).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by JST, the establishment of University fellowships toward the creation of science technology innovation (JPMJFS2106, K. Komaba); JST SPRING (JPMJSP2124, T. Yonehara); and Japan Society for the Promotion of Science (JSPS), Grants-in-Aid for Scientific Research (No. 20K05626, H. Goto).