The influence of the structure of terminal groups and cores on the properties of schiff base star-shaped liquid crystals

A series of star-shaped liquid crystal (LC), respectively, based on phloroglucinol, pentaerythritol and glucose as cores, rod-shaped molecules (<b>MeOSBAA, MeSBAA</b> and <b>ClSBAA</b>) containing a schiff base as mesogenic mesogen were synthesised. The molecular structures were confirmed by FT-IR and ¹H-NMR techniques. The LC textures and thermal phase behaviours were investigated by polarising optical microscopy and differential scanning calorimetry. The results showed that <b>MeOSBAA</b> and <b>ClSBAA</b> were thermally enantiotropic liquid crystals. Three-arm star LC macromolecules <b>X-SBA3E</b> and four-arm star LC macromolecules <b>X-SBA4E</b> were found to display enantiotropic nematic liquid crystals behaviour. While the five-arm star-shaped chiral LC molecules <b>X-SBA5E</b> exhibited enantiotropic chiral nematic phase.