Natural Outdoor Weathering

Since weather varies from day to day, year to year, and place to place, no precise correlation exists between artificial laboratory weathering and natural outdoor weathering. However, standard laboratory test conditions produce results with acceptable reproducibility and in general agreement with data obtained from long-time outdoor exposures. 

Only the 12 row shows natural, outdoors weathering (35,000h) all other figures are related to accelerated weathering, in Q-Sun 3000 (0.35 W/m at 340 nm, 102 18 cycle, 63°C black panel temperature). The data are arranged in the order of decreasing of the yellow component (b) compared to the initial value. 

Krzeminski, D.E., Fernando, D., Gould, T.E., Piland, S.G., Rawlins, J.W., 2012b. Natural outdoor weathering of helmet shell material. Unpublished work. 

Hardcastle HK (2004) Considerations for relating artificial laboratory and natural outdoor weathering durability testing. In Proceedings of the annual technical conference of the society of plastics engineers, Chicago, IL, May 2004... 

Based on the findings of accelerated weathering by xenon tests and natural (outdoor) weathering for films of LLDPE and LDPE resins, it was concluded that PE films containing additives, particularly hindered amine stabilisers (HAS), have a UV stability four times higher than the corresponding pure films [43]. 

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