Degradation

Abstract The degradation of polymers under a wide range of conditions is reviewed. Purely thermal degradation, in inert atmospheric conditions, defines the ultimate stability of a polymer in the absence of other degradative influences. The mechanisms of degradation are shown to include depolymerization, random scission, and rearrangement of functional groups. Their relative importance is dependent upon temperature and polymer structure. Degradation in air is more relevant to service use of polymers and is shown to involve the formation and reaction of hydroperoxides; effects on mechanical properties are reviewed. Photo‐oxidation is shown to be dependent on whether the polymer is intrinsically light absorbing or absorbs via chromophoric impurities. Photoinitiated generation of radicals leads to oxidation chemistry accompanied by photolysis reactions of the products. Degradation by high energy radiation, hydrolytic degradation, and degradation by microorganisms (biodegradation) are briefly reviewed, as are methods of accelerating degradation.