The preparation of copolymerized fluorescent microspheres of styrene using detergent-free emulsion polymerization

The polymerisable fluorescent monomer, 4-ethoxyl-N-allyl-1,8-naphthalimide, was synthesized from 4-bromo-1,8-naphthalic anhydride and characterized using FT-IR spectra, 1H NMR and fluorescence spectra. A copolymer of styrene and 4-ethoxyl-N-allyl-1,8-naphthalimide was prepared by detergent-free emulsion polymerization and characterized using fluorescence spectra, SEM and fluorescence microscopy. The fluorescence spectrum of the copolymer displayed excitation at 365 nm and emission at 435 nm in acetone. SEM revealed that the copolymers were microspheres, with smooth surfaces and displayed intense blue fluorescence.