The Polymer Society of Korea

Abstract

We present C₃-symmetric star-shaped and C₂-symmetric pyrene-cored hexacatenar liquid crystals consisting of triazole moieties, exhibiting hydrogen-bonded helical architectures with axial polarization. In the star-shaped system, GIWAXS analysis and helix simulations reveal a 5₁ helical column with an azimuthal rotation angle of 72°. This assembly enables RT-operable ferroelectric switching, offering potential for high-density ferroelectric random-access memory (FeRAM). Furthermore, in the hexacatenar system, we demonstrate an unprecedented RT-reversible polymorphic transformation between a metastable 8₁ helical columnar phase and a thermodynamically stable crystalline phase. This system exhibits mechanochromism, where mechanical pressure converts the blue-emissive crystalline phase into the green-emissive helical LC phase. Notably, this metastable polymorph can be reverted to the crystalline state via an AC E-field, a phenomenon termed “E-field-chromism.”