Alkyl chains length dependent fluorescence emission and reversible mechanofluorochromism of AIEE-based quinoline derivatives

摘要

Five quinoline derivatives containing different alkyl chains (QLACn, n = 2, 4, 6, 8,12) were synthesized to investigate the effect of alkyl chains on their photophysical properties. The fluorescent properties of the QLACn were affected by the alkyl chains, which indicated obvious blue-shifting trend and fluorescence emission are alkyl chains length-dependent by grinding-induced spectral shifts (Delta lambda(MFC)). Longer alkyl-length revealed larger Delta lambda(MFC). Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) measurements indicated that the transformation between microcrystalline and amorphous states upon external stimuli should be responsible for the observed reversible MFC behavior. (C) 2019 Elsevier Ltd. All rights reserved.