The effect of additives, including antioxidants, ultraviolet absorbers and pigments, on weatherability of colored polyethylene coating has been studied. The colored polyethylene samples of 2. 5 mm in thickness were exposed to a “sunshine type” carbon arc weathering tester, and weatherability was evaluated by the change in their elongation. The results indicated that the weatherability of colored polyethylene depended upon not only antioxidant content but also the UV screen property with pigments and ultraviolet absorbers. After the exposure test, checking grew on the polyethylene surface, and the crack depth was correlated with the screen property. In order to secure the long service life of colored polyethylene, the antioxidant content should be determined according to the UV screen property with both pigments and ultraviolet absorbers.
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