Optimization of Curing Conditions for a Chemical Resistant Tank Coating with the Help of Dynamic Mechanical Analysis

Currently, when the necessary curing conditions for a coating are to be found, the coating is applied to test panels, which are then cured at different temperatures and for different periods of time. The different panels are then immersed in water and other chemicals of interest, at different temperatures. These experiments are time consuming to say the least, as one might have to wait up to a year to get adequate results. By using DMA to investigate the glass transition state (Tg) of the coating one can, with reasonable certainty, decide the needed curing conditions for a coating to be used at a given working temperature.

In addition to the pure temperature factor, it is widely known that postcuring of epoxy paints at elevated temperatures most often will improve a films chemical resistance. This can be explained theoretically, as elevated temperatures increase the reaction rate of curing. The molecules "trapped" at low temperatures can move more freely and therefore react more easily. This will result in a "tighter" polymer matrix and a tighter polymer matrix means less diffusion through the film. Diffusion of molecules through the film is oft