Synthesis and characterization of a low band gap polymer with an aromatic oxadiazole moiety as the side chain

A novel low band gap polymer with an electron deficient oxadiazole side chain, poly[(α-bithiophene-5,5′-diyl) (5′-(2′′-phenyl-1′′,3′′,4′′-oxadiazole-5′′-phenylidene))-block-(α-bithiophene (2′′-phenyl-1″,3″,4″-oxadiazole-5″-phenylidene)quinodimethane-5, 5′-dily)] (PBTBQ-Oid), was synthesized. The polymer was soluble in common organic solvents, such as THF, chloroform and xylene. The structure of the polymer was confirmed by FT-IR, 1H NMR. The optical spectrum revealed that it had maximum absorption among 600–700 nm. The electrochemical analysis showed that it had good electron-transporting properties and a low band gap of ∼1.10 eV.