Synthesis, characterization, and optical properties of new thiophene based copolymer bearing bulky groups

In this study, a new copolymer, based on 4-biphenyl-2,6-bis(4-boromophenyl)pyridine and thiophene 2,5- diboronic ester, has been synthesized via Suzuki cross-coupling reactions. 4-biphenyl-2,6-bis(4-bromophenyl) pyridine was synthesized starting from reaction of 4-biphenyl carboxaldehyde and 4-bromoacetophenone. All of the polymer, monomer and intermediates were characterized using FTIR and NMR spectroscopies. The synthesized polymer exhibit good solubility in common organic solvents. The maximum absorption peak for polymer was 450 nm. The optical band gap energy of the polymer was determined by absorption onset and cyclic voltammetry and found to be 2.7 eV.