The synthesis and luminescence of π-conjugated polymers derived from 3,3′-dicarbazoles

Novel, soluble, π-conjugated copolymers comprising 3,3′-bicarbazole and phenylene or thieno[3,2-b]thiophene comonomer were synthesized using the palladium-catalyzed Heck reaction. The resulting copolymers exhibited good solubility in common organic solvents such as chloroform, chlorobenzene, etc. and good thermal stability. The photoluminescence spectral maxima of the polymers were located at 426 (sh. 454) and 479 nm, indicating that they were blue and greenish-blue emitting materials in solution, respectively. The HOMO levels of the polymers were −5.16 and −5.24 eV and the band gaps were 2.50 and 2.26 eV, respectively.