Phosphorescent side-chain functionalized poly(norbornene)s containing iridium complexes

Norbornenes containing phosphorescent iridium complexes based on Ir(ppy)(3) and Ir(ppy)(2)-(bpy)(PF6) were synthesized and copolymerized with alkylnorbornenes via ring-opening metathesis polymerization in nonpolar solvents using ruthenium initiators. The luminescent properties of the resulting polymers both in solution and in the solid state were tested. The polymers were found to retain the optical properties of the phosphorescent small molecule analogues with emission maxima in the yellow/green, quantum yields from 0.23 to 0.24 for Ir(ppy)(2)(bpy)(PF6) analogues, 0.02 to 0.03 for mer-Ir(ppy)(3) analogues, and 0.20 to 0.24 for fac-Ir(ppy)(3) analogues, and lifetimes of 0.41 to 0.55 mu s for Ir(ppy)(2)(bpy)(PF6) analogues, 0.22 to 0.62 mu s for mer-Ir(ppy)(3) analogues, and 1.28 to 1.48 mu s for fac-Ir(ppy)(3) analogues. By combining the phosphorescent properties of these emissive molecules with the solution processability and ease of synthesis of polynorbornene backbones, these materials might be highly useful in the field of light-emitting devices and emissive display technology.