The degradation can be considered as the result of various reactions
provoked by the stresses of the natural environment (light,
temperature, humidity) of the artifacts. These reactions are likely to
modify the chemical structure of the macromolecules, leading to
the loss of the use properties of the polymer. The elucidation of the
relationship between the modification of the chemical structure
upon irradiation and the degradation of properties such as the
appearance and the mechanical properties, is particularly important
with respect to predicting the fate of the material.