π-Conjugated poly(anthracene-alt-fluorene)s with X-shaped repeating units: New blue-light emitting polymers

A series of new π-conjugated poly(anthracene-alt-fluorene)s with X-shaped repeating units were synthesized. The polymers were easily soluble in common organic solvents and had good film-forming abilities. They showed high absolute PL quantum yields in the solid state. The electroluminescent devices based on the three X-shaped polymers with a configuration of ITO/PEDOT:PSS/polymer/LiF/Ca/Al emitted blue light with high brightness and low turn-on voltages.