Polymers weathering

D. Feldman, Polymer weathering photo-oxidation. J. Polym. Environ. 10, 163-173 (2002)... 

Pospisil J. Nespurek S. Krulis Z. Pilar J. Effect of atmospheric impurities on polymer weathering mechanism and longevity. In Natural and Artificial Ageing of Polymers Reichert, T. Ed. Gesellschaft far Umweltsimulation Pfinztal, Grmany, 2007 pp 125-139. 

Polymer type Impurities in polymer Weather parameters... 

The use of polypropylene (PP) outdoors is limited by its weatherability. The main cause of degradation is photooxidation, promoted by ultraviolet (UV) irradiation, and in hot sunny dimates components made from PP may fail within a few days outdoor service unless they are suitably protected. Failure is usually by brittle fracture resulting from surface embrittlement. Chemical stabilizers added to the polymer can increase the lifetime very considerably and should be used even if a component is to be exposed to sunlight only occasionally. Much of the research into polymer weathering and stabilization has been conducted on PP because of its importance and its sensitivity to outdoor conditions. 

CRITICAL FACTORS AFFECTING PRODUCT PERFORMANCE Material temperature of 250°C should not be exceeded during molding FINISHED PRODUCT PERFORMANCE Provides flame retardancy to the matrix polymer WEATHERING... 

Testing of polymer weathering ( )rmstrong research development center... 

A number of papers are devoted to the study of polymer weathering (Table 10.27). 

Eeldman, D. Polymer weathering photo-oxidation. J. Polym. Environ. 10, 163-173 (2002) Pickett, J.E., Gardner, M.M., Gibson, D.A., Rice, S.T. Global weathering of aromatic engineering thermoplastics. Polym. Degrad. Stab. 90, 405—417 (2005)... 

The photochemical reactivity of polymers is of considerable interest because photodegradable plastics have a number of applications. Additional interest in polymer photoreactivity stems from the need to limit and control weathering in polymer materials. Photodegradation is an important component of polymer weather, and a proper understanding of degradation processes and of the experimental factors that affect degradation is necessary for the accurate estimation of polymer lifetime and for the development of stabilizing systems. 

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