Six novel rod-like bis-ester magnetic liquid crystals have been prepared, in which bis-ester mesogenic cores with n-propyl and n-pentyl substituents were terminated by TEMPO free radical (TEMPO＝2,2,6,6-tetramethylpiperidine-1-oxyl). Their structures were confirmed by elemental analysis, IR and MS. Their magnetic and crystalline properties were determined by a superconducting quantum interference device (SQUID), an electron paramagnetic resonance (EPR) spectrometer, a differential scanning calorimeter (DSC) and a heat stage polarizing optical microscope (HS-POM). Based on those determinations, the molecular structures of those magnetic molecules possessing liquid crystalline property were deduced. The photoelectric property of liquid crystal materials mixed with bis-ester magnetic liquid crystal molecules was also detected. The results show that the six compounds all have both magnetic and crystalline properties; their textures belong to nematic and the temperature range of mesophase is about 16 to 24.8 ℃; and the magnetic liquid crystal molecule could obviously improve the response sensitivity of liquid crystal materials.

Key words: magnetic liquid crystal, ester, 4-OH-TEMPO, photoelectric performance