ABSTRACT
Many kinds of polymeric materials have been developed and used in various industrial fields, and these amounts are increasing. It is said that the amounts of polymeric materials will be over 500/0 of total materials (including metals and ceramics) in the 21st century. These materials are used under the influence of terrestrial sunlight or other artificial light sources. Most polymeric materials have chromophores in the wavelength region of terrestrial sunlight. As a result, the exposure of these materials to sunlight or other light sources causes chemical changes in them, and these microscopic changes induce the deterioration of polymeric materials. Fundamental studies on photodegradation of polymers are required to develop photostable polymers and to estimate the desirable lifetime of the materials. More directly, it is important to develop photodegradable polymers and to solve the polymer litter problem.
