This article describes the homopolymerization of isocyanatoethyl methacrylate (IEM) and its copolymerization with methyl methacrylate (MMA) in acetonitrile in the presence of 2,2-azobisisobutyronitrile. The constant characteristic of IEM polymerizability (k(p)(2)/k(te) = 128 x 10(-3) L mol(-1) s(-1), where k(p) is the propagation constant and k(te) is the termination constant) was determined. The study of IEM reactivity toward MMA gave ratios of 0.88 and 1.20 for IEM and MMA, respectively. The physicochemical properties of the IEM homopolymer and IEM/MMA copolymers were also studied. The glass-transition temperature of poly(isocyanatoethyl methacrylate) was found to be 47 degrees C. From the thermogravimetric analysis of the weight-loss percentage corresponding to the first wave of the thermogram, it was shown that the degradation mechanism of the IEM/MMA copolymers started from the isocyanate group. (c) 2006 Wiley Periodicals, Inc.