Liquid Crystalline Cyclotetraphosphazene

Abstract

Full substituted dodecyloxy derivative of cyclotetraphosphazene was synthesized in order to investigate its mesomorphic properties. Octachlorocyclotetraphosphazene (tetramer) was reacted with dodecanol in tetrahydrofuran (THF) presence of sodium hydride (NaH) as base at room temperature for 24 hours and then under the reflux for a day. Full substituted derivative (1) was obtained and its structure was determined by mass analysis, and by FT–IR, ¹H and ³¹P {¹H} NMR spectroscopic techniques. Additionally, thermal and mesomorphic behaviours were examined by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD) techniques. Obtained results showed that compound 1 has liquid crystal behaviour.

Keywords

• Cyclotetraphosphazene; Liquid crystal; Differential scanning calorimeter; Polarising optical microscopy; X-ray Diffraction

References

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