Two types of donor-acceptor copolymers were designed and synthesized by combination of an electron donor unit of fluorene sequences and an electron acceptor azine unit such as 1,2,4,5-tetrazine and 1,3,5-triazine. They were well soluble in common organic solvents with the number average molecular weight (Mn) of 7.0 and 14.5 kg mol-1, respectively, and have good thermal stability showing about at 360 °C with 5 wt% loss in TGA. Two copolymers exhibited intense blue photoluminescence with emission peak maxima at 437 and 421 nm in CHCl3, and 451 and 422 nm in the film state, respectively. These polymers exhibited good fluorescence quantum efficiencies in CHCl3 (φfl = 0.63, 0.97). Energy levels of the highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels estimated by cyclic voltammetry were to be –5.83, –6.0 eV and –2.85, –2.88 eV, respectively.
International Letters of Chemistry, Physics and Astronomy (Volume 62)
Z. M. Geng and M. Kijima, "Synthesis and Characterization of Fluorene-Based Polymers Having Azine Unit for Blue Light Emission", International Letters of Chemistry, Physics and Astronomy, Vol. 62, pp. 21-28, 2015