Electro-Responsive columnar liquid crystal phases generated by achiral molecules

Abstract

Electro-Responsive columnar liquid crystal (ER-CLC) materials were reviewed, especially ferroelectric columnar materials (FCLC). The history of polar columns are introduced with recent progress toward ER-CLC (electro-responsive columnar) materials. The final part of this review describes a recent study in our laboratory. The insertion of -C6H4-X- (XDOCH2, OCO, NH2CH2, NHCO, N(CH3)CH2, SCH2, CH2CH2, and CHCH) into the Ar-N bonds of bis(N,N0-(3,4,5- trialkoxyphenyl)ureas 4(RDC12H25) was performed, and the compounds with XDOCH2, OCO, NH2CH2, NHCO, N(CH3)CH2, and SCH2 exhibited a CLC phase. The insertion greatly affected their responsiveness and temperature ranges. In the case of 14 (-C6H4-X- (XDOCH2), RDC12H25), the responsiveness was highly improved in comparison with 4. Broad temperature ranges of a CLC phase were achieved by mixing 14 and 19 (-C6H4-X- (XDSCH2), RDC12H25).