Unique electrical, electrochemical and optical characteristics of polyheptadiyne derivatives with long side chains

Conducting of poly(1,6-heptadiyne) derivatives substituted with long side chains containing mesogen units such as poly(bis(4-methoxy-4′-hexyloxybiphenyl)-dipropargyl malonate) (PMHBDPM) exhibit unique characteristics typical to both liquid crystal and conducting polymer. PMHBDPM exhibits novel spectral change corresponding to the electrochemical doping both to polymer main chain and also to the core of mesogen unit in the side chain. Ion diffusion constant evaluated from the doping and undoping characteristics also increases in the temperature range of liquid cystalline phase. Unique dielectric properties and X-ray diffraction characteristics have also been observed in the mixture of PMHBDPM with ferroelectric liquid crystal of low molecular weight.