The 1,3-dipolar cycloaddition reaction was used to assemble fullerene, ferrocene and a second-generation liquid-crystalline cyanobiphenyl-based dendrimer. The targeted compound displayed an enantiotropic smectic A phase from 40 to 135 °C. The d-layer spacing was determined by X-ray diffraction, and was found to be independent of temperature with a value of 95 Å. Molecular modeling and structural considerations suggested partial bilayer organization of the mesogenic molecular units within the smectic layers. Oxidation or reduction processes of the basic components (ferrocene, fullerene, dendrimer) were investigated by electrochemical techniques, and were in agreement with the structure. Photoinduced electron transfer from ferrocene to fullerene was identified, most likely with a “through space” mechanism.

Two novel series of ionic liquid crystal polymers that display proton conductive properties are presented here. These materials are based on linear (l-PEI) or branched (b-PEI) poly(ethyleneimine) functionalized with unsymmetrical oxadiazole carboxylic acids derived from 1,3,4-oxadiazole (1,3,4-OXA_m) or 1,2,4-oxadiazole (1,2,4-OXA_m). The subscript “m” indicates the length of the spacer between the rigid moiety and the carboxyl group, namely m = 4 and 10. The occurrence of proton transfer from the carboxylic acid to the amine groups was confirmed by FTIR and NMR measurements. The liquid crystalline properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction (XRD). All ionic complexes displayed enantiotropic smectic A mesophases and in the case of the l-PEI derivatives a nematic phase was also observed at high temperatures. All investigated derivatives presented good proton conductivity values as determined by electrochemical impedance spectroscopy (EIS). Therefore, these ionic LC hyperbranched polymers represent an effective approach for the preparation of proton-transporting polymeric materials with potential applications in electrochemical devices.