Study of an exhumed HDPE geomembrane used in an industrial water pond: physical and thermoanalytical characterisations

Abstract

This paper analyzed the behavior of an HDPE geomembrane exhumed sample used for 2.25 years as a liner in an industrial water pond from a Brazilian company, as well as another similar sample as a reference. The thermogravimetry (TG) using different heating rates under synthetic air purge gas evaluation showed that the exhumed sample presented a different behavior in the TG curve for a heating rate of 5 C min-1 attributed to the reaction time. The thermomechanical analysis (TMA) curves without purge gas showed the range of thermal stability between 30 and 65 C for the reference sample, which is attributed to a molecular relaxation. The exhumed sample does not have the same relaxation, probably because this sample was submitted to severe environmental conditions in the field. Finally, the physical property values for the exhumed sample showed mechanical brittle behavior, which can indicate that changes probably occurred in the polymer structure.