Accelerated ageing of polypropylene geotextiles, the effect of temperature, oxygen pressure and aqueous media on fibers : Methodological aspects
Résumé
This paper deals with methodological aspects of the accelerated ageing tests used to investigate the thermal oxidation of polypropylene geotextiles. Three ways of accelerating the kinetics are considered: increased temperature, increased oxygen pressure and the immersion of samples in aqueous media. The quality of the simulated ageing test obtained is discussed by comparing the effectiveness of the stabilizers under accelerated ageing with that anticipated from natural ageing. The paper concludes that high temperature ageing tests (about 130 °C) are less representative than tests at more moderate temperatures (80 °C) in which ageing is accelerated by high oxygen pressure and immersion in an aqueous medium. This research highlights how difficult it is to develop a representative predictive test given the lack of long-term site data and the strong links which exist between the extent to which tests are representative, the nature of accelerated ageing and the formulations under study.