Since the strength of geosynthetic clay liners is largely due to the strength of the reinforcing fibers, it is important to understand the long-term behavior of the reinforcement. This paper will address the question of long-term oxidative stability of a polypropylene textile made from fibers used to reinforce a commercial product. Samples were exposed in forced-air ovens at four temperatures for times up to 400 days. The loss of breaking strength and strain were monitored and the temperature dependence of these properties was modeled using 2nd order kinetics. The resulting lifetime prediction suggested that the materials would retain 50% of their strength for 30 years when exposed to air at 20℃. Since the reaction is dependent on oxygen concentration, the rate at 8% oxygen should be several times slower than the rate in air, which means that a service lifetime approaching 100 years is likely in buried applications.
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