Synthesis and characterization of a new yellow-green light-emitting polymer - poly{1,4-bis[3-(4 '-butylphenyl)thienyl]-2,5-di(2 '-ethylhexyloxy)phenylene}

A novel conjugated polymer (PBBPTDEHP), which has a regioregular structure, was successfully synthesized in chloroform using FeCl3 as the oxidizing re agent. The polymer shows good thermal stability and can be easily dissolved in xylene, chloroform, tetrahydrofuran (THF) and other common organic solv ents. Due to the symmetry of the monomer, the polymer formed contains no he ad-head configurational isomers and has high regioregular structure. The st ructure and the purity of the polymer were characterized by FTIR, H-1 NMR, C-13 NMR, MS, and elemental analysis. The absorption edge of the UV-vis spe ctrum of the film sample indicates that the band gap of the polymer is 2.48 eV, which corresponds to yellow-green emission. The polymer shows very sim ilar electrochemical properties to polythiophenes while retaining the synth etic flexibility for substitution found in phenylene. All of the results in dicate that the polymer is a promising yellow-green emissive material for a pplication in light-emitting devices (LEDs). (C) 2000 Elsevier Science S.A. All rights reserved.