The synthesis and characterization of liquid crystalline side chain polymers with mesogenic groups laterally attached to the polymer main chain are described. By variation of the terminal group, mesogenic moiety or spacer length, a change in the glass transition temperature, the nematic to isotropic transformation temperature and the stability of the nematic phase can be achieved. With increasing length of terminal groups, a distinct odd-even effect of the nematic to isotropic phase transformation temperature and also a strong decrease of the glass transition temperature is observed. Macroscopic homeotropic alignment can be achieved in an electric or magnetic field. Conoscopic investigations show optical biaxial behaviour of the nematic phase. A chiral nematic copolymer is the first example of a thermotropic biaxial cholesteric phase.

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Chiral 2-amino-4-alkoxy-5-nitrobenzoate and 5-amino-4-alkoxy-2-nitrobenzoate derivatives as well as the corresponding biphenyl derivatives were synthesized. Some of them were also denvatised to the corresponding acrylates and polyacrylates. Many of the new substances exhibit a large spontaneous polarization and large second order NLO coefficients. In addition some of them show a broad range S z phase. All these properties depend strongly on small changes in the molecular structures. Here we present the synthesis of these novel NLO FLC materials and discuss some of their properties.

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