Dual function of Eosin Y in miniemulsion polymerization: Stabilizer and FRET acceptor

Abstract

Recent studies have shown that water-soluble fluorescent dyes can be used as miniemulsion stabilizers to avoid a series of deficiencies in traditional stabilizers. However, visual means to demonstrate the stabilizing performance of water-soluble dyes are still scarce. In this study, the principle of fluorescence resonance energy transfer (FRET) is combined with dual emission of fluorescent polystyrene nanoparticles prepared by miniemulsion polymerization. For this purpose, 4-(1,2,2-triphenylethyl) phenylundecene-10-enoate (TPE-Aly) was employed as aggregation induced emission (AIE) dye and donor and Eosin Y as acceptor and stabilizer. The polymer molecular weight, particle size and size distribution of the nanoparticles were optimized by regulating the amount of Eosin Y and ultrasonication time, respectively. The average number of Eosin Y molecules per nanoparticle was firstly estimated by combining dialysis and Lambert-Beer law. FRET between TPE-Aly and Eosin Y indicates the presence of Eosin Y on the surface of the polymer nanoparticles. With increasing concentration of Eosin Y, the as-prepared dual-emission nanoparticles display a decreasing particle size along with an enhancing FRET efficiency. Moreover, various stability tests show that Eosin Y can be used as an excellent stabilizer for miniemulsion polymerization and has broad application prospects in the field of functional materials research.