Synthesis and properties of novel liquid crystalline compounds having fluorinated ring systems

摘要

To satisfy the current requirements for better quality of the liquid crystal displays (LCDs), the three series of liquid crystalline (LC) compounds having fluorine substituted chroman ring systems have been prepared and evaluated. These chroman compounds were synthesized through their individual ring closure reaction as a key step. All of the compounds show high dielectric anisotropy (Delta epsilon) and high birefringence (Delta n), but the significant different solubility is shown between two similar compounds having two fluorine atoms on chroman ring system. The solubility to the base mixture consisted of fluorinated compounds depends oil the position of fluorine atoms on the core structure. We suggest that the difference of the solubility is caused by the two parameters: the melting enthalpy and the structure.