Preparation and characterization of functional near ultraviolet fluoresent microspheres

Abstract

The polymerisable fluorescent monomer, allyl carbazole, was synthesized from carbazole and characterized using FT-IR spectra, 1H NMR and fluorescence spectra. Using allyl carbazole as fluorescent dye, carboxyl polystyrene fluoresent microspheres, polyacrylamide fluorescent microspheres and polystyrene fluoresent microspheres with sulfonic groups with narrow particle size were prepared by dispersion polymerization. These fluorescent microspheres were characterized by SEM, fluorescence microscopy, FT-IR spectroscopy, the conductivity, fluorescence spectrophotometry and UV-vis spectrometer. The results indicated that the three kinds of fluorescent microspheres with good dispersion and stability and high blue fluorescence intensity were obtained. And carboxyl groups, sulfonic groups and amino groups were successfully introduced on the surface, whose contents were approximately 45, 90 and 60 μmol g−1, respectively. Furthermore, the characteristics of allyl carbazole should be maintained in the fluorescent microspheres, the difference of the spectra between fluorescent microspheres and allyl carbazole in ethanol and toluene were also proved.