Degradation and stabilisation of blue water pipe

Degradation caused by natural and artificial exposure of blue polyethylene water pipe compounds has been studied using thermal, spectroscopic and mechanical testing techniques. The results indicate that whilst thermal properties can be used as an effective quality control tool, deterioration of mechanical properties corresponds rather more with carbonyl index measurements. Samples in thin and thick sections have been studied and differences in behaviour are noted, with thick section samples retaining mechanical (impact) properties even after substantial degradation has occurred. Limitations in the use of artificial exposure to monitor changes that occur during natural weathering are discussed. It is concluded that, in thick section, the surface nature of ultraviolet degradation in the extreme conditions of artificial exposure affects mechanical properties in a different manner than longer-term periods of natural exposure.