Blue-light electroluminescence from p-phenylene vinylene-based copolymers

Electroluminescence (EL) in the blue region of the spectrum with a maximum at 465 nm was observed from polymer films sandwiched between indium-tin-oxide and Al electrodes. The specially designed soluble multiblock copolymers used consisted of chromophoric units that have uniform conjugation length and are spaced with polymethylene units of various lengths. EL originates from the radiative decay of the chromophore singlet excitation created as a result of the recombination of injected charge carriers.