Schematic illustration of amide-functionalized polydiaryfluorene and characterization of hydrogen bonds. (a) Hydrogen bonds among the neighbouring chains. Chemical structure of P (ODPF-co-ADPF) and the schematic illustration on the intermolecular hydrogen bonds. (b) Variable temperature FT-IR spectra of P4 ranged from 30°C to 200°C: the 1600-1700 cm-1 region due to C=O vibrations, 3100-3600 cm-1 region due to N-H vibrations. (c) Synchronous 2D-FTIR correlation spectra of P4 as a function of temperature, calculated with software of 2Dshige according to the spectra data of C=O (top) and N-H (right).