Synthesis and liquid crystal properties of 2,5-bis (4-Alkylphenyl)‎ thiazolo (5,4-d)‎ thiazoles

الملخص EN

A new homologous series of 2,5-bis(4-alkylphenyl)thiazolo[5,4-dJ thiazoles has been prepared, where alkyl groups are represented Cn H2n+|-.

The methly and ethyl compounds (11 and 12) of this series are nematic, while the higher members (n>3) are polymesomor-phic.

A plot of the solid-liquid crystal-isotropic transition temperatures against the number of carbon atoms in the alkyl group shows the usual odd-even effect.

Interphase transition between solid, mesomorphic and isotropic phases were studied by hot-stage microscopy and differential scanning calorimetry (DSC).

The effect of replacing the phenyl ring in central linkage with a hetrocyclic ring are discussed.

A preliminary determination of the type of texture by polarized microscopy is also included.