Performance of colored HDPE geomembrane exposed to tropical climate

AUTHORS: Satinee Srikwanma, Colin Lim, and Hermann Ng

The use of coloured geomembrane (GMB), particularly light-coloured ones, has gained significant popularity in recent years due to its superior thermal performance. These materials exhibit reduced wrinkles and lower degradation rate under exposed condition as compared to conventional black GMB. In this study, three (3) different high density PE GMBs in different colours (black, white and tan) and one (1) linear low-density PE GMB (green) having thickness ranging from 1.5 mm to 2.0 mm were exposed to Malaysian tropical weather for at least two & half years. Surface temperatures were monitored & recorded periodically during the exposure.

The results indicate a lower temperature registered in the reflective white followed by tan, green and black. Oxidative induction time (Std-OIT & HP-OIT) tests were subsequently conducted on samples retrieved at defined intervals (up to 36 months) to further evaluate durability. These tests establish the depletion profile throughout the exposure duration and provide insights into the thermal performance and durability of each PE GMB. In general, both white & tan GMBs retained most antioxidants after weathering with white outperforming the tan in HP-OIT. Besides, light coloured (green) LLDPE experience degradation faster than all HDPE suggesting higher degrees of crystallinity in HDPE minimize solar weathering.