Time-temperature-transformation analysis of an alkyd-amino resin system

The curing of a thermoreactive alkyd-melamine-formaldehyde resin system was investigated by rheologycal, TG and TMA-analysis, in order to Construct the time temperature transformation diagram. The points of the gelation Curve were determined by measuring the increase ill Viscosity during isothermal Curing at different temperatures. A power-function could be fitted to the gelation Curve, which is suitable to estimate gelation at any curing conditions, as well as to establish storage conditions. The reaction in the resin matrix was followed by monitoring the loss of mass during isothermal Curing at different temperatures. The final section Of the resulted iso-curing temperature (iso-T-curc) diagrams could be fitted with logarithmic functions, which may be used for estimating the conditions needed to a given, desirable mass loss, i.e. conversion. The steepness of the curves increases with temperature suggesting the forthcoming of degradation during Cure With increasing temperature. From these data the iso-mass loss curves of the TTT-diagram were constructed. For determining the iso-T-g curves of the TTT-diagram isothermal curing was carried out in a drying oven at different temperatures, followed by TMA measurements. The iso-T-cure diagrams served to determine T-ginfinity, and to construct the iso-T-g curves of the TTT diagram. Vitrification curve is far beyond conditions of storage, Curing and degradation, meaning that the resin matrix is in rubbery physical state before, during and after the cure. Curing conditions resulting degradation call also be estimated from the TTT-diagram.