Accelerated test method for resistance of plastics to nitrogen dioxide

Abstract

The discoloration produced by the exposure of plastics to a polluted atmosphere containing nitrogen oxides and other gases is well known. New formulations with increased resistance to such discoloration require reliable accelerated tests for characterization of additives and products. The new procedure is based on an exposure of plastics to an atmosphere with a controlled concentration of nitrogen dioxide and evaluation of subsequent discoloration by optical measurements.