Degradation Behavior of Two Multilayered Textured White HDPE Geomembranes and Their Smooth Edges

Abstract

The longevity of two white multilayered textured geomembranes, manufactured with a smooth edge for welding, is examined when immersed in synthetic municipal solid waste leachate at five temperatures (40, 55, 65, 75, and 85°C) for 50 months. The textured and smooth parts of the geomembranes had similar initial chemical and physical properties, but the core of the smooth edge was thinner. It is shown that, depending on the relative effects of the difference in the core thickness and the surface area exposed to a solution, antioxidant depletion of the textured portion may be either faster or slower than the smooth edge. However, due to the lesser core thickness of the smooth edge of both geomembranes, the degradation in the tensile stress at break properties at 85°C is faster for the smooth edge than for the textured portion of the roll even when the antioxidant depletion was faster for the textured part. Thus, any assessment of the likely service life of the textured geomembrane requires consideration of both the smooth and textured portions of a multilayered textured geomembrane.