From Table 4 it can be deduced that both the modulus of elas- ticity and the tensile strength were not significantly affected by the ageing process in the first reprocessing cycle, even after 600 h in the QUV chamber, which is equivalent to 22.1 years outdoors. Nevertheless, for samples reprocessed five times (Table 5) the mod- ule of elasticity decreased slightly, whereas the tensile strength decreased drastically during the first 400 h of residence in the QUV chamber (approximately 33% of its initial value), and remaining practically constant thereof.
These studies reveal that, in general, the major difference in the behaviour among the reprocessed materials took place in the