Synthesis and Characterization of Conjugated Polymers Based on Thieno[3,4‐b]Thiophene Quinoidal Unit

Abstract

AbstractDriven by the success of quinoidal units for enabling high‐performance polymer semiconductors, herein a new quinoidal building block that terminated by indandione is reported. By introducing Br atoms into the terminal benzene rings of indandione, two CPs, P2TbTI‐DPP and P2TbTI‐TIID, are synthesized through Stille polycondensation. The strong electron‐withdrawing ability of indandione‐terminated quinoidal unit enables P2TbTI‐DPP and P2TbTI‐TIID with low‐lying LUMO energy levels of ≈–3.90 eV. Organic thin‐film transistors based on P2TbTI‐DPP and P2TbTI‐TIID exhibit n‐type transport behavior. Besides, it is found that the electron mobility of these two polymers is weakly dependent on the annealing temperature due to the near‐amorphous of polymer thin‐film.