Polymeric Ultraviolet Absorbers

Abstract

Abstract Plastics used in outdoor applications are exposed to the harmful solar radiation between 290 and 400 nm. Fortunately, the ozone layer of the outer atmosphere protects the earth's surface from the higher energy radiation below 290 nm. The intensity of solar radiation at the surface of the earth is at a maximum in July and a minimum in January due to changes in the thickness of the ozone layer. The intensity also varies with the time of day, location, and weather conditions.