Modification of bituminous binders with styrene-butadiene- styrene copolymer and sulfur

The object of research is bituminous binders modified with styrene-butadiene-styrene and sulfur. The purpose of this work is to study the physical and technical properties of polymer-bitumen binders modified with sulfur. The influence of styrene-butadiene-styrene and sulfur on the physical and technical properties and short-term aging of the polymer-bitumen binder is considered. Method. Tests of bitumen and polymer-bitumen binders were carried out according to the following indicators softening point, dynamic viscosity at 105 °C, 135 °C and 165 °C, penetration at 25 °C, extensibility at 0 °C, Fraas brittleness temperature, as well as the difference in softening temperature after aging in the RTFOT oven. Results. The dependences of the influence of sulfur on high-temperature and low-temperature properties, as well as on the short-term aging of bitumen and polymer-bitumen binder based on styrene-butadiene-styrene copolymer have been established. It was found that with an increase in the sulfur content in bitumen, the difference in softening temperature after aging in the RTFOT furnace increases. However, the modification of the polymer-bitumen binder with sulfur gives the opposite effect, up to negative values due to the destruction of polysulfide bonds as a result of thermal exposure and dynamic shear.