Problem Solving Forum
June 17 - June 21, 2019
What is the effect of the wind-chill factor on the curing of epoxy and PU when temperatures are similar?
Marco Fabio Ramenzoni of ZINGA METALL BRASIL on
June 19, 2019:
It is known that solvent-based coatings (usually o ...read more It is known that solvent-based coatings (usually one-component), that cure thru the evaporation of solvent, dry faster due to the faster evaporation of the solvent with the increase of the wind speed. Therefore, one could assume that two-component (even one-component that cures not through evaporation of solvent) epoxy or PU, with some solvent content, would cure faster on windy days, too. The mechanisms that cures the two-component epoxy or PU are different from the evaporating solvent drying mechanism. Usually, the two-component cure mechanisms accelerate with the increase of temperature. As the evaporation of the solvent (or any liquid including water) takes energy from the environment which it is in, this environment loses energy with the evaporation of solvent, lowering the temperature as a result. So, finally, with lower temperature, usually the curing reactions slow down, increasing the time of total cure on windy days, opposed to what one could think at first.