Synthesis and electro-optical properties of blue emitting poly(BP-alt-BCV) conjugated polymers

A new blue electroluminescent conjugated polymer, poly(BP-alt-BCV), was prepared by Hornor-Emmons polycondensation of [5-carbazol-9-yl-3-(diethoxy-phosphorylmethyl)-2(2-ethyl-hexyloxy)-benzyl]-phosphonic acid diethyl ester (PHBP) and 4,4'-biphenyldicarboxaldehyde (BPCA) in the presence of tert-BuOK in THF. UV-visible absorption maximum (lambda(max), UV, pi-pi* transition) of poly (BP-alt-BCV) was measured at 340 nm. PL maximum (lambda(max,PL)) values of poly(BP-alt-BCV) were obtained at 406 and 430 nm, when excited at its own lambda(max,UV). It was found that double layer [ITO/poly(BP-alt-BCV)/Alq(3) (50 angstrom)/Al] PLED exhibited maximum EL peak at 440 nm and blue emission (x = 0.1794, y = 0.1878), similar to the NTSC standard blue (x = 0.14, y = 0.08).