Ultraviolet light accelerated tests

Accelerated weathering tests are performed in special test chambers all of which are similar in that a coated specimen is exposed in a controlled environment containing a high intensity ultraviolet light source and a facility for spraying water onto the test surfaces. 

Emulsion polymers and commercial controls were milled (Table III) and molded (Table IV) to produce test samples, and properties were evaluated following standard ASTM procedures (Tables V-VII). During accelerated ultraviolet light aging, the polymers were also examined by infrared spectroscopy of films cast from o-dichlorobenzene solution (Table VIII). 

Hirt RC, Schmitt RG, Searle ND, Sullivan AP. Ultraviolet spectral energy distribution of natural sunlight and accelerated test light sources. J Opt Soc Am 1960 50(7) 706-713. 

Of considerable interest in recent years is the laboratory simulation and acceleration of atmospheric pollution effects to evaluate degradation of materials. These tests involve injection of a variety of gases, vapors, and particulate matter into a controlled pressure chamber with controlled condensation on metal specimens. Sometimes, ultraviolet light is used to produce photochemical changes in the gases or vapors to replicate smog conditions. 

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