Solar radiation, polymer weathering

Although polymers vary widely in their resistance to photodegradation, almost every polymer deteriorates on continued exposure to solar radiation during outdoor weathering. 

Solar radiation plays an important role in weathering of polymers. This fact even more complicates the transformation of antioxidants. Because ROO-CHD s contain both a peroxidic bond and a carbonyl group in one molecule, they take part in the... 

Virtually all polymers deteriorate under exposure to outdoor weathering and solar radiation, but at greatly varying rates. Polymers In solar equipment must maintain optical, mechanical, and chemical Integrity despite prolonged exposure to solar ultraviolet radiation. For most outdoor applications of polymers, solar radiation exposure Is Incidental, but for many solar applications, exposure to solar radiation Is deliberately maximized In the equipment design. Transparency Is essential for many of the potentially most cost-effective applications, and conventional approaches to ultraviolet protection such as opaque coatings and fillers are unacceptable. 

Plastic films exposed to natural weather undergoes photo-oxidative reactions. Sunlight, together with oxygen, initiates the chemical reactions in the polymer matrix. The important aspects of sunlight include sunshine duration, total solar radiation, and UV radiation that may be used in modeling of the degradative processes [6-8],... 

Molded parts made from non-colored PES yellow and embrittle - as do most aromatic polymers - relatively rapidly when exposed to weathering. The negative effect of UV light in solar radiation can be reduced by adding active carbon black [694]. 

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