Unveiling the Effects of Interchain Hydrogen Bonds on Solution Gelation and Mechanical Properties of Diarylfluorene-Based Semiconductor Polymers

Hydrogen bond effects on solution gelation, viscosity, and crystallization. (a) The semidilute toluene solution of P1-P4 (10 mg/mL) before and after aging at room temperature for 10~20 min. (b) Normalized intensity correlation function () of P1-P4 in dilute toluene solution (0.5 mg/mL), measured at the scattering angle of 90^o. (c) The hydrodynamic radius () distributions of P1-P4 in dilute solutions calculated from dynamic light scattering (DLS) measurements. (d) Rheological measurement for P1-P4 in 10 mg/mL toluene solution: their respective shear sweep viscosity as a function of shear rate. (e) Wide-angle X-ray scattering (WAXS) data for P1-P4 drop-coated films. (f) Crystallization dominated polymer films and schematic representation of the edge-on molecular packing in the crystalline region.