Synthesis and characterization of liquid crystal trimers based on laterally attached terphenyls

Liquid crystal trimers consisting of a laterally attached terphenyl in the center and two terminally attached mesogenic groups at both ends have been synthesized. The thermal and phase behavior of these trimers were studied u sing DSC and polarized light microscopy methods. It is shown that incorpora ting laterally attached terphenyl rods into these trimers does not eliminat e liquid crystallinity although it destabilizes the mesophase to some exten t. In addition, increasing the length of the terminally attached rods resul ts in a more stable mesophase, It is concluded that in the nematic phase th e laterally attached rods are forced to orient in the nematic field directi on of the terminally attached rods.