In the presence of imprinting molecules of sulfadiazine, two kinds of molecularly imprinted polymers ( MIPs) were synthesized by photoinitiated and thermally initiated polymerizations, respectively. The combination of sulfadiazine and alpha-methyl acrylic acid and their composite ratio were studied by differential UV absorption spectrometry. The results show that a combined effect between the functional monomer and the imprinting molecule occurred in the solution. The structure and properties of these synthetic polymers were researched and compared with IR spectroscopy, transmission electron microscopy, and a balanced combination of static experiments. The polymer materials synthesized in these two ways had the same molecular structure, but their morphology was different. Furthermore, through the adsorption isotherm, Scatchard analysis, and evaluation of the imprinting efficiency, we determined that the lower temperature was a more suitable synthesis condition for the polymerization of the MIPs. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 3189-3198, 2011