LIFE PREDICTION METHODOLOGY ON WEATHERABI LITY FOR COLOR POLYETHYLENEHEAVY-DUTY COATING

The method for service life prediction of color polyethylene heavy dut y coating has been studied from the behavior of antioxidants in polyet hylene. Color polyethylene samples of 2.5mm in thickness were exposed to the environment in Japan and Saudi Arabia for 2 years. Antioxidant concentration profiles after the exposure test were obtained by the me asurement of oxidative induction time. An antioxidant consumption and diffusion model constructed in an artificial accelerated exposure test was applied to the natural environments, and the adequacy of this mod el was proved in the natural environment as well. The change in elonga tion of color polyethylene coating as a function of time in natural en vironmental conditions was calculated by using the model function comp utation and the correlation between the degradation depth and elongati on of the polyethylene coating. This method quantitatively predicts th e service life on weatherability in natural environments for color pol yethylene heavy duty coating.