LIQUID-CRYSTALLINE GELS OF POLYAMIDE NETWORKS WITH STIFF SEGMENTS AND FLEXIBLE JUNCTIONS

The preparation of a novel family of "liquid-crystalline" polyamide network gels is described. In these networks, the segments are stiff and longer than the critical axial ratio for mesomorphic behavior. The junctions are trifunctional and flexible. The gels are intensely birefringent in the relaxed nascent state, unlike fully rigid or fully flexible gels. The birefringence of the present gels is clearly associated with the coexistence in them of both long, stiff mesogenic segments and flexible trifurcated junctions. Thermal studies of the gels indicate very strong attractive interactions between the networks and the solvent.