A new fluorescent copolymer, poly(1-vinylimidazole-co-(1-pyrene) methyl 2-methyl-2-propenote) (VI-co-PyMMP), has been designed and synthesized by a free-radical copolymerization of VI and PyMMP as well as characterized using ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR), 1H NMR, and fluorescence spectroscopies. The monomer reactivity ratios are determined by two methods of Fineman-Ross (r1 = 0.28 +/- 0.04 for VI, r2 = 1.32 +/- 0.11 for PyMMP) and Kelen-Tudos (r1 = 0.23 +/- 0.05, r2 = 1.22 +/- 0.12). Based on the reactivity ratios, the monomer sequence lengths and Q and e for PyMMP monomer are further calculated. The results suggest that the copolymerization of VI and PyMMP is a nonideal copolymerization without an azeotropic point (i.e., r1 < 1, r2 > 1 and r1r2 < 1) and has a low alternation tendency. The conclusions drawn in this work may not only direct the later synthesis of the copolymers but also enrich the database of free-radical copolymerization. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012