Synthesis and Properties of Novel Copolymers Based on Fluorene and Thiophene

<正>1 Results In this contribution we present the synthesis and characterization of novel copolymers based on fluorene and thiophene (see Scheme 1).They were synthesized by the Pd-catalyzed Suzuki coupling reaction of 9,9-dihexylfluorene-2,7-diboronic acid bis(1,3-propanediol) ester and 3-substituted (R=3-methylbutyl,hexyl,2-(pyren-1-yl)vinyl) 2,5-dibromothiophenes and characterized by GPC,IR and NMR techniques.UV-vis absorption,photoluminescence (PL) and electrochemical behavior of these polymers were also studied.Though a similar absorption was observed in solutions and thin films of the polymers,the maximum at 400 nm for FIPT and F3HT and at 390 nm FPyT,PL of FPyT thin film differs from those of FIPT and F3HT thin films.They exhibited an intense green PL emission,whereas PL emission of FPyT thin film was orange with a red-shifted maximum compared with FIPT and F3HT indicating pronounced aggregation of FPyT in the solid state.Cyclic voltammetry showed that all the polymers are reversibly oxidized and reduced.A similar electrochemical behavior was observed for FIPT and F3HT whereas a higher electron affinity was estimated for FPyT.