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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.

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.

The synthesis and phase behaviour of liquid-crystalline acrylates and chloroacrylates wii h side-on fixed mesogenic groups are described. Polymers which have similar mesogenic group but whose polymer backbones differ in chemical constitution exhibit identical liquid-crystallirie to isotropic phase transformation temperatures (T,). The glass transition temperature (T!:) decreases with increasing flexibility of the main chain and with increasing length of the terminal groups of the mesogenic side groups. All polymers with side-on fixed mesogenic groups exhibit a nematic phase. The domain texture indicates biaxial nematic phase behaviour. In copolymers consisting of mesogenic and non-mesogenic monomers, nematic phase behaviour is still observed, T, is strongly depressed, and Tg is similar to that of the non-mesogenic homopolymer.

Polymeric additivess have a great influence on the processing parameters in the produciton of high‐performance ceramics. The various types of additives are described and the interactions between the organic additives and the inorganic ceramic powders, some examples of which are shown in the figure, are examined with emphasis on one of the most important ceramic forming processes.