The Effect of Sulfur on different Properties of SBSModified Bitumen

Nowadays, using of SBS modified bitumens due to their favorite physical, mechanical and rheological properties increased in pavements and asphalt applications. But some defects of these binders such as high viscosity, instability in storage tank and etc. lead to several problems in use of these binders. Using of sulfur can solve this problem. The application of sulfur whit SBS in bitumen mixtures is considered to improve the binder properties by reducing the binder’s temperature susceptibility. This research investigated the interaction effects of sulfur/polymer as a function of various blending treatments in the laboratory. For this study, PMBs with sulfur binders were produced using six blending times (5, 10, 15, 25, 35 & 45min), three blending temperatures (160, 170, and 180°C), and three sulfur contents (3, 3.5 and 4% by weight of polymer content). The results from this study showed that (1) The interaction time and interaction temperature for binders had significant effect on the binder properties; (2) With the going of the time more than 15 min, good properties will be lost (softening point, PI); (3) More percentages of sulfur content led to higher viscosity because of higher vulcanization; (4) The 160°C temperature is not suitable temperature for 6%SBS modified asphalt with every percentage of sulfur and in this temperature a gelcomponent may be formed

Keywords:

polymer modified bitumen , sulfur , curing process , Rheology