Production and method optimization of fluorescent polystyrene

Polystyrene (PS), when used as a substrate, reacts with acetyl chloride through the Friedel–Crafts mechanism to yield fluorescent acetylated polystyrene. Different acetylated polystyrene microspheres can be obtained under different experimental conditions. The fluorescence of acetylated polystyrene is observed via fluorescence microscopy, while the quantum yield of acetylated polystyrene is determined using a steady-state transient fluorescence spectrometer. The surface morphology is observed via scanning electron microscopy, and the chemical composition and structure are investigated by Fourier infrared spectroscopy, ultraviolet spectrophotometry, X-ray diffraction, and nuclear magnetic resonance spectroscopy. Finally, the optimal reaction conditions are determined as follows: carbon disulfide (CS 2 , 35 mL), aluminium chloride (AlCl 3 , 1.161 g), acetyl chloride (AC, 1.171 g), soaking time of 12 h, temperature of 50 °C, and water bath for 5 h. Under these conditions, the acetylated polystyrene exhibited obvious fluorescence, with good fluorescence stability and coverage. Furthermore, it exhibited acid and alkali resistance, low-temperature resistance, and light resistance, and did not produce fluorescence leakage. In addition, it could be used as a tracer in organisms.