BLUE ELECTROLUMINESCENT DEVICES WITH HIGH QUANTUM EFFICIENCY FROM ALKOXY-SUBSTITUTED POLY(PARA-PHENYLENE VINYLENE)-TRIMERS IN A POLYSTYRENE MATRIX

We report electroluminescence of electroluminescent devices fabricated from cis,trans-2,5-dimethoxy-1,4 -bis[2-(3,4,5-trimethoxyphenyl)ethenyl]benzene blended in a polystyrene matrix as emission layer. This choice of materials avoids the inherently poor miscibility of polymers with other compounds and minimizes interactions between the host polymer and the electro-optically active guest, which can produce quenching sites. A blue light-emitting device with high internal quantum efficiency (approximately 1%) results.