V-shaped Schiff’s base liquid crystals based on resorcinol: synthesis and characterisation
收藏资源简介：
This paper designed and synthesised a series of V-shaped liquid crystal molecules (<b>X-SBA<sub>n</sub>E</b>) with resorcinol as the core and Schiff base as the mesogenic arms (<b>X-SBAA</b><sub><b>n</b></sub>). The effects of polarity of terminal groups (X=-CH<sub>3</sub>O,-CH<sub>3</sub>,-Cl) and length of flexible chain (n = 4,6,8) on mesogenic ranges were discussed. The chemical structure of <b>X-SBAA</b><sub><b>n</b></sub> and <b>X-SBA<sub>n</sub>E</b> was studied using FT-IR and <sup>1</sup>H-NMR while their thermal behaviour and mesogenic ranges were investigated via differential scanning calorimetry (DSC) and polarising optical microscopy (POM). The results indicated that <b>X-SBAA</b><sub><b>n</b></sub> containing OCH<sub>3</sub> and Cl substituents exhibited mesophase except for the analogue having CH<sub>3</sub> substituent which was found to be non-mesogenic. All of the synthesised <b>X-SBA<sub>n</sub>E</b> had liquid crystal properties and exhibited nematic phases in heating and cooling. The length of the flexible spacers and terminal groups significantly influenced their mesogenic ranges.
