The effects of natural ageing on the solar absorptance of paints exposed in three Brazilian cities
DOI:
https://doi.org/10.46421/entac.v20i1.5895Keywords:
Natural aging, Solar absorptance, Solar reflectance, Weathering, PaintAbstract
This paper evaluates the differences in the solar absorptance (αsolar) of paints after one year of natural aging in the cities of Teresina, São Carlos and Florianópolis, with samples exposed facing the 4 cardinal points. The solar reflectance of each sample was measured using a spectrophotometer with an integrating sphere, and the αsolar calculated from this, for the new paints and after one year of aging. The data showed that, for all the cities, the black color showed more uniform behavior considering the location and solar orientation, as well as the greatest differences in αsolar after aging. In Teresina, the samples showed less variation than in the other cities. In general, for the lighter colors, the variations between each orientation were significant. It was observed that there are differences in the way αsolar paints are altered during the natural ageing process, and that the climate and local characteristics are variable according to the exposure site, which interferes with this alteration.
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