Donor–Acceptor Conjugated Copolymers Containing Difluorothienylethylene-Bridged Methyleneoxindole or Methyleneazaoxindole Acceptor Units: Synthesis, Properties, and Their Application in Field-Effect Transistors

• DOI: 10.1021/acs.macromol.8b01297
• Publication Date: 2018-09-06T18:36:52Z
• Authors: Yankai Zhou; Shiying Zhang; Weifeng Zhang; Jianyao Huang; Congyuan Wei; Hao Li; Liping Wang; Gui Yu
• Keywords: Planarity testing; Acceptor; Fluorine; Electron Mobility

We report the synthesis and characterization of two novel difluorothienylethylene-bridged methyleneoxindole (FVTI) methyleneazaoxindole (FVTAI) acceptor units six FVTI- or FVTAI-based donor–acceptor (D–A) copolymers P1–P3F. On basis optimized conjugated backbone conformations, we put forward intramolecular noncovalent interactions existing in these suggested that fluorine pyridine-nitrogen atoms could improve polymeric planarity by forming multiple conformation locks such as N···H, F···H, F···S interactions, etc. Thin film microstructure investigations indicate with more their respective single D–A pair generally formed orderly thin films. All exhibited p-type charge transport characteristics increasing mobilities from P1 to P1F P2 P2F. contrary, P3F showed relatively lower mobility than P3, which was attributed higher hole injection barrier for P3F-based field-effect transistor device.