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

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