Effect of polymers on rheological properties of waxy bitumens

Abstract

The definition of bitumen wax has been formulated to facilitate the distinction between harmful wax and less harmful or non-harmful. Since exact behaviour of waxes within bitumens is not completely determined and the absence of cooperative study related to modification of bitumens involving different amounts of waxes, the values found in the study are thought to be useful in determining which content of wax and type of polymer would be better for the needs of petroleum refineries in different countries. The scope of this study is to minimize the negative effects of waxes within bitumens obtained from different sources. For this purpose, modified bitumen samples were prepared by using different types of polymers such as elastomers, plastomers and polyethylene groups. Following the determination of the contents of wax by Differential Scanning Calorimetry and TS EN 12606-1, rheological properties of waxy bitumens and polymer modified bitumens (PMB) were evaluated using dynamic shear rheometer tests. The intermediate temperature performance levels of PMB were also determined by fatigue parameters. Besides, rutting performance of PMB was evaluated using Zero Shear Viscosity and Multiple Stress Creep Recovery tests.