X-ray Diffraction from Side Chain Liquid Crystal Polymerst

X-ray diffraction results are reported on a number of side chain liquid crystal polymers with polymethylsiloxane and polyacrylate backbones. Identifications of the phase types have been made and models for the local packing of the mesogenic units proposed. Most of the smectic polymers with terminally cyano-substituted side chains show the partially overlapping structure common in their low molecular weight analogues, but for polymer liquid crystals this structure is not confined to cyano-compounds. The temperature dependence of the intensity of the smectic layer reflection and the layer spacing is discussed.