New Silicon‐Containing Polyquinolines: Synthesis, Characterization, and Electroluminescence

This study reports the synthesis, characterization, and electroluminescent device application of three new silicon-containing polyquinolines: poly(2,2'-(bis(p-phenyl)-diphenylsilane)-6,6'-bis(4-phenyl quinoline)), poly(2,2'-(bis(p-phenyl)octylmethylsilane)-6,6'-bis(4-phenyl quinoline)), and poly(2,2'-(bis(p-phenyl)diphenylsilane)-6,6'-bis(4-hexylquinoline)). The polymers with alkyl side chains were soluble in organic solvents. The new polymers showed robust thermal properties with glass transitions of 161-339 °C. Cyclic voltammetry of the polymers revealed quasi-reversible reductions with onsets of -1.55 to -1.71 V (vs SCE) and corresponding electron affinities of 2.69-2.85 eV. Organic light-emitting devices using new polyquinolines as emissive materials showed blue (CIE coordinates =0.21, 0.20) or blue-green (0.23, 0.36) electroluminescence with a moderate brightness (140 cd m -2 ) and efficiency (0.04%). The results demonstrate that silicon-containing polyquinolines are promising n-type wide band-gap semiconductors for organic electronics.