Synthesis and Properties of Liquid-Crystalline Polymers with Laterally and Terminally Linked Mesogenic Units

Within the class of dimesogenic liquid-crystalline polymers, series of new LC-polyesters with laterally and terminally linked mesogenic units were synthesized. The mesogenic moieties perpendicularly arranged to the main chain are endowed either with identical or with unequal wing groups. Depending on the wing group and the spacer length, the polyesters can form monotropic or enantiotropic nematic and smectic phases. These polymers were subjected to characterization studies using optical microscopy, differential scanning calorimetry and X-ray diffraction techniques. The phase behavior is compared with that of combined and cross-shaped polymeric mesogens.