Three Classes of New Chiral Dopants: Synthesis and Physical Qualification as Dopants for Practical FLC-Mixtures

Abstract

Three classes of new chiral dopants were synthesized and their properties in a non-chiral host mixture were measured. An extremely large spontaneous polarization (77 nC/cm 2 at 25°C) was induced by 10% dopant in one case. Molecular mechanics calculations reveal that such a high polarization is predominantly obtained by steric hindrance around the chiral center. This steric effect also influences other physical properties such as helical twisting power. In addition the relationship between electro-optical properties and spontaneous polarization (Ps) are studied. It is apparent that higher Ps does not always improve switching time and bistability.