Preparation process to affect stability in waste polyethylene-modified bitumen

Abstract

An analysis of waste polyethylene (WPE) modified bitumens prepared using a variety of approaches is described in this study. The WPE was obtained from commercially-available packaging bags. It has recently been shown that addition of WPE to bitumen enhances the high temperature stability of the modified bitumen. In this paper, WPE-modified bitumens were prepared using a high-speed shear mixer employing different processing parameters. High temperature storage stability tests and morphological analysis showed that a shear rate of 3750rpm, at 150°C and shear time of 1.5h to be the optimal processing parameters of storage stability. In addition, differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) were used to analyze the thermal stability of the WPE-modified bitumen. We found that the thermal stability of the modified bitumen surpassed that of the base bitumen, but was generally independent of the preparation parameters.