Effects of Titanium Dioxide on the Structure and Properties of Bitumen

Abstract

The aim of this work was an evaluation of the influence of titanium dioxide on the chemical and physical properties as well as the aging behavior of bitumen. Accordingly, two samples of paving grade bitumen 50/70 and one polymer modified bitumen sample 25/55-55 A were modified with two different titanium dioxide products. These bitumen samples were investigated in different modification and aging states, to evaluate the photocatalytic and filler effects of the titanium dioxide. The investigation procedure included different analytical methods, like Fourier Transform infrared spectroscopy, asphaltene separation, thin layer chromatography, as well as different physical methods like the determination of the softening point ring and ball and needle penetration along with investigations with a dynamic shear rheometer. The results did not show any negative effects of the titanium dioxide on the properties of bitumen. In contrast, a positive influence on bitumen aging could be recognized in regard to different chemical and physical parameters. However, the extent of the property changes depended on the types of bitumen and titanium oxide used.