Effect of spacer on the hybrid liquid crystalline phase in binary polymer blends of side-chain liquid crystal polymers.

Abstract

By mechanical mixing method, we prepared binary side-chain liquid crystalline (SCLC) polymer blends composed of cyanobiphenyl (CB) polymethacrylate with varied alkylene spacers and azobenzene (Az) polymethacrylate with decylene spacer. The polymer blends exhibit higher isotropic temperatures compared to each homopolymer by differential scanning calorimetry and polarized microscope observation. The blends were revealed to exhibit the smectic (Sm) E phase at room temperature by X-ray scattering measurement. Each homopolymer does not exhibit the SmE. These results indicate the induced highly ordered smectic phase formed by the binary mixture of the SCLC polymers. On the other hand, the DSC curve of the polymer blend with relatively low molecular weights of 6000-8000 was almost unchanged through the isotropic temperature.