Poly(2-alkoxy-p-phenylene)s as deep-blue light-emitting polymers

A series of light-emitting polymers, poly(2-alkoxy-p-phenylene)s (RO-PPPs), was synthesized by nickel-catalyzed coupling of 2,5-dichloro-alkoxybenzene, which has intense deep-blue photoluminescence (peak at 412 nm) from the solid film and has good solubility in common organic solvents. The light-emitting diode was constructed with the single emitting layer structure ITO/RO-PPP/Ca/Ag having a turn-on electric field of 1.3 × 106 V/cm and brightness over 30 cd/m2 at a current density of 7 mA/cm2.