The kinetics of the copolymerization of N-isopropylacrylamide (NiPAAm) and diethylene glycol monomethylether monomethacrylate was followed by online H-1 NMR spectroscopy. Two copolymerization reactions were sufficient to evaluate the kinetic data with the Extended-Kelen-Tudos method as well as the nonlinear least square method. The copolymerization parameter was determined as r(NiPAAm) = 0.70 and r(DEGMA) = 2.0. The higher reactivity of the methacrylate compared to the NiPAAm is in good agreement with other kinetic data of similar systems. (C) 2004 Wiley Periodicals, Inc.