Chirality in some liquid crystalline association chain polymers
Two series of sequence random association chain liquid crystalline polymers have been synthesized by melt mixing a bispyridyl with dicarboxylic acids, which in their individual states are not liquid crystals. The phase behavior of two classes of polymer complexes was examined using hot stage polarized light microscopy. It is shown that polymer complexes consisting of (+)-3-methyl adipic acid exhibit a chiral nematic fingerprint texture even at low molar concentration (1.5%) while polymer complexes with an (L)-tartaric acid derivative exhibit a weak fingerprint texture only at high concentration. The effects of the random association chain structure on the thermal behavior of the polymer complexes are also discussed.