Evolution of five exposed geomembranes to climate conditions in Portugal throughout 12 years

Abstract

To study how the properties of high density polyethylene geomembranes, exposed to climatic conditions, evolve throughout 12 years, a parametric study was carried out. Parameters under study included: (i) different geomembranes exposed in several regions of Portugal, aiming to assess the influence of climatic conditions; (ii) geomembranes exposed in locations with different ultraviolet index, in order to verify the influence of that index; (iii) the exposed samples, covered with and without geotextile, to evaluate the influence of such as a protection for geomembranes. The properties studied were: density, melt flow index, tensile properties, carbon black content, and oxidative induction time. The results show that the properties of the geomembranes exposed to climatic conditions present some deterioration, especially regarding the oxidative induction time and density. As for the geomembrane exposed in locations with different UV index, it suggests that the increase of this index impacts the tensile properties and oxidative induction time. Finally,