Affiliation:
1. GeoSolutions Consulting Inc., Vancouver, Canada
2. Department of Civil Engineering, Queen's University, Kingston, Ontario, Canada
Abstract
The depletion of antioxidants from a 2 mm high-density polyethylene geomembrane immersed in brine at seven temperatures (95, 85, 75, 65, 55, 40, and 25°C) for 28 months is reported. An Arrhenius model is used to predict the performance of the geomembrane at low site-specific temperatures. The antioxidant depletion times are reported for temperatures between 20 and 95oC. The solubility of the antioxidant and stabilizer packages, the oxidation by-products, and their susceptibility to hydrolysis are discussed. After 28 months of incubation, no oxidative degradation was observed for samples in the full brine solution even at 95oC. Morphological changes reduced the stress-crack resistance to a stable representative value without a reduction in the tensile elongation at break. The effect of the brine solution concentration on the depletion of antioxidants and stabilizers was investigated at 85°C. It was found that the depletion rate decreases with the increasing brine concentration.