Thermal properties of polymers made from the copper(l)-catalyzed cycloaddition reaction between azides and alkynes have been investigated. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were used to measure the glass transition temperatures (T-g) of these materials. The polymers were found to have unusually high T-g values, up to 60 degrees C higher than the curing temperature. It has been shown that the increase of T-g was time dependant, thus, depending on the state of cure of the material. (c) 2006 Elsevier Ltd. All rights reserved.