New ladder‐type conjugated polymer with broad absorption, high thermal stability, and low band gap

Abstract

Abstract New ladder‐type π ‐conjugated polymer poly{6‐alkyl‐pyrrolo[3,2‐b:4,5‐b′]bis‐[1,4]benzothiazine} ( PPBBTZ ) was synthesized through a simple method. PPBBTZ showed good solubility in organic solvents (such as chloroform, tetrahydrofuran, chlorobenzene, o‐dichlorobenzene) and high thermal stability (decomposition temperatures up to 323 °C and 299 °C in nitrogen and air, respectively). The highest occupied molecular orbital and lowest unoccupied molecular orbital energy level estimated from electrochemistry result and absorption spectrum were −5.46 and −3.81 eV, respectively, with a band gap of 1.65 eV. More interestingly, PPBBTZ displayed broad absorption from ultraviolet to visible light regions (200–750 nm). These properties suggested PPBBTZ was a good candidate in opto‐electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012