Effects of perfluoration of epoxy-amine polymer matrices on the electro-optical performance of polymer dispersed liquid crystal films

Polymer dispersed liquid crystal (PDLC) films were obtained by combined the rmally and polymerization induced phase separation processes initiated by t he temperature controlled polycondensation reaction of monomers carrying ei ther epoxy or amine groups. The epoxy diglycidyl ether of bisphenol A (DGEB A) and two different amines very used: an aliphatic amine and an aromatic f luorinated amine. The nematic liquid crystal mixture E7 was employed. The e lectro-optical performance of the obtained PDLC films was analyzed as a fun ction of reaction cure in the absence and presence of the fluorinated amine . It was found that the addition of the fluorinated amine has a strong infl uence on the transmission vs voltage curves. A remarkable decrease of thres hold- and saturation voltages as well as an increase of the transmission va lues in the on-state was observed.