4-Chloro-3-methylphenyl methacrylate (CMPM) and 2,4-dichlorophenyl methacrylate (2,4-DMA) were synthesized by reacting methacryloyl chloride with 4-chloro-3methylphenol (CMP) and 2,4-dichlorophenol (2,4-DP), respectively. Homo and copolymers of CMPM and 2,4-DMA were obtained from different monomer feed ratios, using 2,2'-azobisisobutyronitrile as initiator in toluene at 70 degrees C. IR-spectroscopy was employed to characterize the resulting homo and copolymers. Copolymer compositions were determined by ultraviolet (UV) spectroscopy. Fineman-Ross method was used to calculate the reactivity ratios of the monomers. Average molecular weight and polydispersity index were obtained by gel permeation chromatography (GPC). Thermogravimetric analyses (TGA) and differential thermal analysis (DTA) of copolymers were carried out under a nitrogen atmosphere. Antimicrobial effects of the homo and copolymers were also investigated for various microorganisms such as bacteria, fungi, and yeast. (c) 2006 Wiley Periodicals, Inc.