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Polymer science is, of course, driven by the desire to produce new materials for new applications. The success of materials suchas polyethylene, polypropylene, poly(vinyl chloride) and polystyrene is such that these materials are manufactured on a huge scaleand are indeed ubiquitous.It is widely recognized that ultraviolet rays in sunlight (wavelengths between 280 nm and 400 nm) is an important factorcausing photodegradation to some organic substances such as polymers.UV radiation causes photooxidative degradation which results in breaking of the polymer chains, produces free radical and reducesthe molecular weight, causing deterioration of mechanical properties and leading to useless materials, after an unpredictable time.In order to protect against the damaging effects of UVR on polymers, addition of UV light absorbers, excited state quenchers,hindered amine light stabilizers (HALS), hydroperoxide decomposers, radical scavengers, pigments, fillers and antioxidants are aneffective and convenient solution in practice.

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Emad Yousif graduated from Baghdad University, Iraq, in 1996 with a BSc in chemistry. He then transferred to Al-Nahrain University, also in in Baghdad, to study for his MSc and PhD,and graduated in 1998 and 2004, respectively.Yousif´s research covers the inorganic, photochemistry, synthesis, structure, processing and properties of polymers.

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