INDUCTION OF THE SMECTIC PHASE IN THE POLYMER COMPLEXES BETWEEN ELECTRON-ACCEPTING IONIC NITROSTILBAZOLES AND ELECTRON-DONATING LIQUID-CRYSTALLINE POLYMERS

A new type of miscible polymer complex was prepared from electron-accepting trans-N-alkyl-4-nitro-4'-stilbazolium bromides or iodides and electron-donating polymers containing a mesogenic (carbazolylmethylene)aniline. The 1:1 (mole ratio) polymer complexes showed smectic behavior. For example, the 1:1 polymer complex of trans-N-hexyl-4-nitro-4'-stilbazolium bromide and the electron-donating polyacrylate exhibited a smectic A phase from 75 to 140 degrees C, although the smectic phase did not appear in both individual components. The isotropic temperature of these polymer complexes increased with increasing carbon number of the alkyl chain in the nitrostilbazolium bromide. Similar tendencies on the thermal behavior were observed for the complexes of the ionic nitrostilbazoles and a low-molecular-weight nematic compound containing the same carbazolyl group. It was concluded that the miscibility and the induction of the smectic phases are caused by the complex formation between the ionic nitrostilbazole group and the nonionic mesogenic (carbazolylmethylene)aniline group by ionic and electron donor-acceptor interactions.