High-efficiency fluorescent polyimides based on locally excited triarylamine-containing dianhydride moieties

Abstract

Three novel high fluorescent polyimides (PIs) were readily synthesized from the polycondensation of triarylamine-based tetracarboxylic dianhydride monomers with a commercially available aliphatic diamine monomer. The photoluminescence (PL) intensity of the solid film and the nanofiber fabricated by solution casting and electrospinning methods revealed high quantum yields of up to 32% and 35%, respectively. Furthermore, in order to investigate the fluorescent transition mechanisms of the PIs, a series of model compounds corresponding to the repeat units of PIs were also synthesized, and density functional theory calculation results were also used to support the deduction. Moreover, the competition of aggregation enhanced emission (AEE) and aggregation caused quenching (ACQ) effects was investigated and demonstrated.