Liquid crystalline side group polyesters with a systematic variation of main chain and side group spacer length

To investigate the influence of a systematic variation of the length of mai n chain and side group spacers on the thermal phase behaviour four homologo us series of liquid crystalline side group polyesters with 4-(phenylazo)azo benzene moieties as mesogenic side groups have been prepared and characteri zed. The polyesters exhibit smectic and/or nematic phases. The mesomorphic properties were studied by using optical polarizing microscopy, differentia l scanning calorimetry (DSC) and X-ray diffraction. Packing models of the l ow ordered smectic phases have been derived from X-ray data.