Effect of pigments and additives on organic binder’s weather resistance

The effect of pigments and additives on the resistance of organic binders to cyclic changes in temperature, humidity, and UV radiation intensity was investigated. The study involved paints based on two binders used in polyurethane paints, pigmented in various shades of yellow, red, and blue. Both the binders and pigments differed in their weather resistance. The color stability, gloss, water contact angle, and surface energy of the coatings were assessed. Changes in color and gloss depended primarily on UV radiation, while decorative properties depended on the type of pigments in each color group. Smaller changes in color and gloss were caused by changes in humidity and temperature, without the contribution of UV radiation. The more weather-resistant pigmentation protected the binder from degradation, as confirmed by FT-IR.