Thermotropic liquid crystalline conjugated polymers, poly(cyclohexylphenoxyacetylenes) - synthesis and properties

Summary form only given. A, series of poly(cyclohexylphenoxyacetylenes) that are mono-substituted polyacetylenes with liquid crystalline group in the side, chain have been synthesized to elucidate systematically phase transition behaviors and optical and electrical properties of the polymers. Since the side chain of the, polymers consists of cyclohexylphenoxy moiety as a rigid mesogen, a methylene chain as a spacer, and a terminal alkyl group as a flexible moiety, the polymers are abbreviated as PPCHn03A ( n = 2, 3, 5, 6, 7, and 8). The polymerizations are carried out using not oaly Ziegler-Natta and metathesis catalysts but also rhodium complex catalyst. Special attention has been paid to the identification of liquid crystalline states of the substituted acetylene monomers and polymers during observation of optical textures in the polarizing microscope and also DSC measurement. Charge transfer interaction between the polyene main chain and iodine, used Es a chemical dopant is elucidated by means of UV-Visible absorption spectra. Macroscopic alignment of die polymer due to the external force such as shear stress or magnetic force has been focused in relation to enhancement of electrical conductivity upon iodine doping.