PA30 Thermal Properties and Liquid Crystal Formation of Linear Polyurethane With Mesogenic Groups

Abstract

Liquid crystalline polyurethanes (LCPUs) having amino groups were synthesized from amphiphilic liquid crystalliine compounds. Their thermal and orientational properties were examined by polarizing microscopic observation, DSC and the X-ray diffraction. The amphiphilic liquid crystalline compounds formed smectic and nematic phases. The smectic layer structures with both hydrophilic and hydrophobic sublayer were formed through a microphase segregation. LCPUs synthesized from the amphiphilic liquid crystalline compounds exhibited a nematic phase. A bending behavior of fibers and films of LCPUs was observed through UV light irradiations due to photoisomerization of azobenzene moieties.