Synthesis, liquid crystal property and gelation ability of semi-fluorinated 4-alkoxyphenyl 4-alkoxybenzoates

Abstract

ABSTRACTThis paper describes the synthesis and physico-chemical properties for 4-(4-perfluorohexylbutoxy)phenyl 4-alkoxybenzoate (compounds 1-n), and the results are compared with the corresponding hydrocarbon derivatives (compounds 2-n). Compounds 1-n show exclusively a smectic A (SmA) phase, where the SmA–isotropic phase transition temperatures are 142°C for 1-1 and 147°C for 1-6. The SmA phase is characterized using a polarized microscope and DSC measurements. Interestingly, compound 1-6 forms gels in n-octane, ethanol, and aprotic polar solvents such as acetonitrile and γ-butyrolactone, while compound 1-1 shows no-gelation ability. The n-octane gel is characterized by scanning electron microscope (SEM) observation, showing nano-fibers assembled with compound 1-6.