Polymeric materials environmental weathering tests

Severe exposure conditions significantly reduce service life. Thus, the service life of unprotected PE in the dark at 20°C is 8-10 yr, and of stabilized or crosslinked PE in a moderate climate is 15-20 years [7, 13]. In India, Pakistan, or Saudi Arabia, where the sun intensity is greater (250 kW cm ), the weathering life is only 2-5 yr, even if the products (pipes, tubes) contain much more antioxidants (2%). For other PE products (films), the lifetime in Saudi Arabia is only 3 months, while in Florida it is twice as long [14—16]. Temperature variations in the environment can also be a potential factor for the degradation of the polymeric material, diminishing the lifetimes of the products. These factors are especially important in climates with large differences between summer and winter temperatures (tests for these environmental... 

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