Plastics and the Chemical Environment

Polymers are subject to degradation which is caused or accelerated by chemical agents. Many polymers are actively attacked by pollutants 

Sulfur dioxides, hydrocarbons, nitrogen oxides, and particulate matter such as sand, dust, dirt and soot are known to be common air pollutants. These atmospheric pollutants may cause degradation in combination with solar radiation and other weather factors. Sulfur dioxide is a pollutant that arises from industrial sources and soot is acidified by the interaction with moisture and other particles in the presence of sulfur dioxide and oxygen. 

Acrylic, nylon and polyester are especially susceptible to hydrolysis and metals, such as iron and copper, catalyse this degradation. Metal impurities which are present as a result of the manufacturing process, or in a composite material, accelerate degradation. Many polymers are alkali and acid sensitive, and acid can cause the hydrolysis of polymer chains. Organic vapours and fumigants can dissolve or swell plastics. 

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