Free films of 4 acrylic and 4 alkyd wood coatings were used to study their water-vapour permeability, elasticity, hygroscopity and the glass transition temperature. The FTIR spectra of hardened coatings were also recorded. The coatings were exposed to accelerated artificial weathering as well. It was found out that the alkyd coatings had lower water-vapour permeability and hygroscopicity than the acrylic ones. Using the weathering process the water-vapour permeability and the hygroscopicity decreased, and the elastic properties aggravated for all the coatings. The glass transition temperature of the alkyd coatings increased more than that of the acrylic ones, and after the weathering process the temperature of all the coatings raised. After weathering, there were no visible changes in infrared spectra.
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