Blue emitting polymers as host materials of phosphorescent dopant and their electroluminescent properties

Abstract

Two types of blue electroluminescent conjugated polymers, poly(BP- alt -BCV) and poly(BFMP12-BPV), were prepared by Horner-Emmons polycondensation and used as host polymers for the phosphorescent dopant, (bsn)(2)Ir(acac). Poly(N -vinylcarbazole) (PVK), known as a blue emitting material, was also used for comparison with these polymers. Electrophosphorescence of PLEDs with these dopant/host systems was investigated in terms of luminescence, efficiency, emission color, and energy transfer. The poly(BP- alt -BCV) showed blue emission of high color purity (x = 0.18, y = 0.19), however, poly(BP- alt -BCV) host/phosphorescent (bsn)(2)Ir(acac) dopant showed red emission (x = 0.60, y = 0.37) due to an efficient energy transfer from poly(BP- alt -BCV) host polymer to phosphorescent (bsn)(2)Ir(acac) dopant.