Effects of chiral additives on the electro-optical properties of polymer dispersed liquid crystal

• 1,1′-binaphthyl-2,2′-diol with strong chiral structure was used as chiral molecule.
• Effects of chiral additives on the electro-optical properties were discussed.
• The interaction mechanism of chiral inducement was discussed and confirmed by SEM.

Five polymer dispersed liquid crystal films were prepared using 1,1′-binaphthyl–2,2′-diol as the chiral additive with different concentration. These liquid crystal films showed us different electro-optical (EO) properties. Through theoretical analysis and discussion, the relationship between the electro-optical properties and the concentration of 1,1′-binaphthyl–2,2′-diol chiral additive was revealed. As the concentration of the chiral additive increasing, the mesh size of the liquid crystals would become smaller; so the liquid crystal molecules would become harder to be oriented in the electric field and therefore, the threshold voltage and saturation voltage would increase; the open state response times were also extended; the off state response times would be reduced.