Novel Blue Light Emitting Poly(N-arylcarbazol-2,7-ylene) Homopolymers: Syntheses and Properties

In this paper, we synthesized a new type of poly(N-phenyl-2,7-carbazole)s with alkoxy groups or a diphenylamino group at o-, m-, or p- position of the N-phenyl group using the Ni(0)-catalyzed Yamamoto polymerization in high yields. The series of structural isomers were synthesized in order to optimize the inter- and intramolecular interactions. The electron-rich triethylene oxide groups or the triphenylamino groups were introduced to tune the HOMO energy levels. These polymers were characterized by 1H NMR, 13C NMR, IR, elemental analysis, GPC, TGA, UV−vis, fluorescence spectroscopy, and electrochemical analysis. All the polymers had enough high molecular weights to show a good solubility in common organic solvents and a good processability for making thin films. Deiodination of the terminal residual iodide of the polymers enhanced the fluorescent quantum yields in CHCl3 (φf (sol) = 0.8). In the form of thin films, all the polymers displayed the fluorescence charts with emission bands around 430, 455, and ...