ASTM D5721-08(2018)

4.1 Under the severe conditions of this test, the specimens undergo degradation at a rate that is a function of the thermal endurance of the geomembrane under examination.

4.2 The elevated temperature for this practice should represent conditions that are sufficiently severe to induce failure of polyolefin geomembranes within an abbreviated period of time.

4.3 The rate of change of a particular property as a function of temperature may be evaluated using the temperatures and times outlined in Practice D3045.

4.4 Any correlation between this practice and natural life of these materials must be determined for the particular application in which the materials are to be used.

4.5 Air-oven aging can be used to evaluate and compare the performance of various heat stabilizer packages.

1.1 This practice covers a means for estimating the resistance of polyolefin geomembranes to thermal aging in the presence of air. Only the procedure for heat exposure is specified, not the test method or specimen. The effect of heat on any particular property may be determined by selection of the appropriate test method and specimen.

1.2 This practice should be used as a guide to compare thermal aging characteristics of materials as measured by the change in some property of interest. This practice does not predict thermal aging characteristics where interactions between stress, environment, temperature, and time control failure.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.