Synthesis and characterization of new π-conjugated polymers containing 1,8-naphthyridine in the main chain: Role of the 1,8-naphthyridine unit in π-conjugated polymers

摘要

Alternating π-conjugated copolymers of 1,8-naphthyridine-2,6-diyl (1,8-Nap) with 9,9-dioctylfluorene-2,7-diyl (P(Flu-Ph-1,8-Nap)) and 2,5-didodecyloxy-1,4-phenylene (P(ROPh-Ph-1,8-Nap)) have been synthesized by Pd-catalyzed organometallic polycondensation. The copolymers showed UV-vis absorption peaks at around 390 nm in o-dichlorobenzene. The polymers were photoluminescent both in o-dichlorobenzene and in the solid state. In o-dichlorobenzene, the emission peaks of P(Flu-Ph-1,8-Nap) and P(ROPh-Ph-1.,8-Nap) appeared at λ_(EM) = 440 and 471 nm, with quantum yields of 87% and 66%, respectively. Electrochemical data revealed that 1,8-Nap behaved as a typical electron-accepting unit. When P(Flu-Ph-1,8-Nap) was treated with 10-camphorsulfonic acid, the emission peak shifted to λ_(EM) = 598 nm.