Abstract
Polyethylene is well known as a good chemical-resistant material and is widely utilized in practice. In lining applications, some types of modified polyethylene are developed and used as a lining for the purpose of substrate protection from corrosive environments. In this paper, the degradation behavior of a new modified polyethylene (sPE) lined on a steel substrate exposed to hydrochloric acid (HCl) solution environment was investigated. Diffusion behavior of the HCl solution, adhesion strength, and blister formation with time dependence were considered as key parameters of the degradation behavior. Influences of elevated temperature (80°C to 15°C and 40°C to 15°C, corresponding to the inner and outer sides of the lining system) and the concentrations of the HCl solution (0, 5, 10, 15, and 20% in mass) on the key parameters were studied. Diffusion of the solutions into the polymer was strongly affected by its concentration and temperature. Chloride element was found in the interface of the polymer and substrate by the use of energy-dispersive x-ray spectrometry (EDS). No blister was observed after 2,800 h exposure time. The adhesion strength data obtained from the peeling test showed the significant influences of temperature elevation and concentration of HCl solution on delamination.
