Triphenylene-Based Polymers for Blue Polymeric Light Emitting Diodes

An efficient synthesis has been developed toward I novel series of conjugated blue emitting Polymers containing triphenylene as repeating unit for PLEDs. Soluble 1,2,3,4-tetraphenyltriphenylene, 2,3-bis(4-octylphenyl)-1,4-diphenyltriphenylene, 2-heptyl-1,3,4-triphenyltriphenylene, 2-decyl-3-(4-octylphenyl)- 1,4-diphenyltriphenylene, and 2,3-diheptyl-1.4-diphenyltriphenylene-based co- and homopolymers have been synthesized by the palladium-catalyzed Suzuki-Miyaura and the nickel-catalyzed Yamamoto polycondensation reactions, respectively. The photophysical properties of the polymers Were Studied based oil the different main chains and substituents. Because of the twisted phenyl rings around the triphenylene main core, pi-pi stacking ill the polymers was prevented, resulting in almost identical photoluminescence (PL) spectra in both Solutions and films. All polymer,, exhibited narrow emission in the range of 430-450 nm, where the human eye is most sensitive for the blue range.