scope:

This guideline will address the (ageing) effects of weather-induced stress1) on thermoplastic products that can result from the impact of radiation (UV, VIS, IR), alternating humidity and dampness, as well as temperature changes, i.e., for the scenarios in which plastics are used in outdoor areas, as well as for use in indoor areas.

The effects of stress collectives will not be addressed here when they play a secondary role in relation to the influence of weather (e.g., the simultaneous impact of corrosive gases or mechanical stress). While degradation that is induced solely by thermal stress is addressed in guideline VDI 3822 Part 2.1.5, temperature has an influence on all chemical reactions due to the temperature dependency of the reaction rate constant. This includes an influence on the reaction product distribution (competition of individual reaction rate constants with different temperature dependencies).

Comprehensive descriptions of the weathering of polymers and the identification of weathering effects can be found in [1; 2].