Modulating the Luminescence Properties of Coronene Molecules via Inclusion Complex Formation with Helical Syndiotactic Poly(methyl methacrylate)

Abstract

The formation of nanocavities that can confine molecules in limited spaces is crucial for controlling the arrangement, aggregation, reactivity, and function of molecules. It is also one of the foundational elements of molecular systems in life. Herein, we demonstrate that the helical structure of syndiotactic poly(methyl methacrylate) (st-PMMA), a synthetic polymer, functions as a nanocavity that confines coronene, as a guest molecule, in the nanospace, thereby controlling the luminescent properties of coronene. Inclusion complexes are formed between st-PMMA helices and coronene molecules in toluene, as confirmed by UV-vis, DSC, and XRD. When encapsulated within the st-PMMA helical cavity, coronene molecules in a low-dimensional arrangement exhibit aggregation-induced emission and the observed fluorescence is red-shifted.Additionally, when a quencher, C₇₀, is introduced as a second guest molecule into the st-PMMA/coronene inclusion complex gel, C₇₀ is encapsulated within the st-PMMA helical cavity, resulting in the selective quenching of only the aggregationinduced emission of the encapsulated coronene.