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Abstract
We report the synthesis of polycatenar liquid crystals incorporating 2,5‐disubstituted Citation1 Citation3 Citation4‐oxadiazole and Citation1 Citation3 Citation4‐thiadiazole rings joined by a combination of carbon–carbon single and double bonds (–CH = CH–). The ratio of the aromatic core to the aliphatic chains was varied systematically by changing the number of the aliphatic chains, from two to six, and their length, from short to very long, i.e. from methoxy to hexadecyloxy. The shape anisotropy of the core was varied by exchanging the oxygen atom in the Citation1 Citation3 Citation4‐oxadiazole for a sulfur atom to form the corresponding Citation1 Citation3 Citation4‐thiadiazole ring with a smaller deviation from coaxiality of the bonds in the 2,5‐positions. The shape anisotropy of the core was increased by the presence of an additional phenylenevinylene unit in a series of tetracatenar oxadiazoles. We report the synthesis, physical properties and polymerization of a polycatenar reactive mesogen in a columnar phase to form a polycatenar polymer network.
Acknowledgments
We express our thanks to the EPSRC for funding. The University of Hull is also thanked for postgraduate studentships (GJR and CW). We would also like to thank B. Worthington (1H NMR) and K. Welham (MS) for spectroscopic measurements.