Synthesis and study of some imidic and new Schiff-base polymers

The work includes the synthesis of two types of polymers: liquid crystalline polymers and thermally stable polymers. Two new series of liquid-crystalline polymers having differing mesogenic moieties (Polyimide esters and Schiff-base polymers) have been prepared and their properties examined. The two series of liquid-crystalline polymers show multiple endotherms in melting to the liquid-crystalline phase and the spacer length was found to have a marked effect on the mesophase and the phase transition temperatures. The polymers exhibit nematic phase, some of the Schiff-base polymers though they show nematic phase, yet they showed homeotropic behaviour. 13 tabs.; 32 figs.; 70 refs