Copolymers of N(-1,1-dimethyl-3-oxobutyl)acrylamide (DOBA) and Methyl methacrylate (MMA) were prepared in dimethylformamide using benzoylperoxide as the initiator at 70 °C. They were characterized by IR, 1H NMR, and 13C NMR. Copolymer compositions were determined by the analysis of 1H NMR spectra. The weight and number average molecular weights of the polymers were determined by size exclusion chromatography. Monomer reactivity ratios were found to be 1.52 for MMA and 0.43 for DOBA according to Kelen-Tüdos method. Glass transition temperatures of the copolymers were determined by differential scanning calorimetry. The initial decomposition temperatures of the polymers were about 215°C as measured by thermogravimetric analysis under nitrogen atmosphere. Swelling properties of the polymers were measured in distilled water. Maximum water uptake of about 70% was observed for poly(DOBA). In case of copolymers, water uptake decreases with the increase of MMA content in the polymer chain. © 2013 Taylor & Francis.