A mixture of diglycidylether of bisphenol A (DGEBA) and gamma-butyrolactone (gamma-BL) was cured in the presence of ytterbium triflate as a catalyst. The kinetics of the various elemental processes that occur in the curing process were studied by means of isothermal curing in the FTIR spectrometer. The kinetics of the contraction during the curing was also evaluated by TMA. In both cases, the kinetics was analyzed by means of isoconversional procedure and the kinetic model was determined with the so-called compensation effect (isokinetic relationship). The isothermal kinetic analysis was compared with that obtained by dynamic curing in DSC. We found that all the reactive processes and the contraction follow a surface-controlled reaction type of kinetic mechanism, R-3. (C) 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 381-393, 2004.