“…Another study was conducted on predicting the service life of HDPE 100 pipes under thermal aging using comparisons of the mechanical behavior of this material in the presence/absence of antioxidants, the activation energy, and the shift factor by the oxidation index method ("OIT") (Eddine et al, 2000). Studies by researchers (Celina et al, 2005;Fouad, 2010 ;Al-Bayaty et al, 2020;Varley et al, 2000;Choi, E et al, 2020 ;Dorleans et al, 2021) report that the degradation of HDPE under temperature leads to a change in mechanical and physical behavior at temperatures between 40°C and 120°C, after these temperatures the results of the degradation of this material may be erroneous. The degradation of polymeric materials can focus on the variation of elongation at break, tensile strength, and density (Loos & Dara, 1987 ;Rühl et al, 2017 ;Kurtz et al, 2002).…”