N,N-Bis(4-alkyl and alkoxyphenyl) terephalamides의 합성과 액정성

Synthesis and Liquid Crystalline Properties of N,N-Bis (4-alkyl and alkoxyphenyl) terephalamides

The synthesis and properties of two new series of compounds having aromatic amide mesogenic units are reported. Most of these new compounds are thermotropic mesogens. In consideration of the fact that aromatic amides form crystals of high melting point which is unfavourable for the formation of thermotropic liquid crystals, we make use of terminal alkyl and alkoxy groups to decrease the melting temperature. In order to investigate the influence on properties of the terminal groups, different alkyl and alkoxy groups are used at the two ends of the rod-like molecules. The results indicate that appropriate terminal substitution is essential for the aromatic amides to form thermotropic liquid crystals.