Polyfluorene and its derivatives as electroluminescent materials

As an important class of electroluminescent polymers, polyfluorene and its derivatives have been paid much attention because they have advantages of easy modification and high photoluminescence efficiency. As a whole in this review, the chemical modification is aimed at developing new electroluminescent materials through tuning frontier molecular orbitals, thermal and luminescent stability. The focus in this review is on the relationships between the structures of polymers and their light emission properties. The synthesis methods of the polymers are first concisely introduced. Then the polymers have been divided into two kinds according to the difference of chemical structure. The one is the polymers that the main conjugation chains are only comprised of fluorene units, whose chemical modification are based on the active C9 of fluorene moiety. The other is the polymers that the main chains are comprised of fluorene and other functional groups through copolymerization.