Light-Emitting Properties of Fluorene Based Copolymers

Abstract

A series of random copolymers of 2,7-dibromo-9,9-bis(4′-n-octyloxyphenyl) fluorene (BOPF) and 2,7-dibromo-N-(2′-ethylhexyl)carbazole (EHC) were synthesized through Ni(0)-mediated polymerization. Carbazole comonomer was introduced to improve the hole-transporting properties of PBOPF. The synthesized poly(BOPF-co-EHC)s showed similar UV-visible absorption and PL emission to PBOPF. EL devices were fabricated in an ITO/PEDOT/polymer/Ca/Al configuration. EL devices which used copolymers showed improved device performance over devices which used PBOPF homopolymers due to a more balanced charge transport.