The properties of SBS-modified asphalt binder in the presence of dithiodimorpholine and tetraethyl thiuram disulphide

Abstract

Sulphur and its compounds are effective to be used as crosslinking agents for polymer-modified asphalt (PMA) binders to solve the separation of styrene–butadiene–styrene (SBS) triblock copolymer and asphalt binders. In this paper, the properties of SBS-modified asphalt binders were investigated after adding two kinds of disulphides, dithiodimorpholine (DTDM) and tetraethyl thiuram disulphide (TETD). It is clear to observe that the addition of DTDM and TETD strongly affects the properties of SBS-modified asphalt binders, such as the softening point, penetration, storage stability as well as the rheological properties. As both of them were added into the PMAs, their high-temperature property and storage stability were highly enhanced at proper content and ratio of DTDM and TETD, especially as the ratio of DTDM and TETD is 2:1 or 1:2. DTDM and TETD may have chemical reactions with SBS and asphalt binder, and network structure was likely to form. The mixtures of DTDM and TETD could be used as a favourable additive of PMA binders.