SBS/Carbon Black Compounds Give Asphalts with Improved High-Temperature Storage Stability

Styrene-butadiene-styrene tri-block copolymer (SBS) modified asphalts are usually unstable during high-temperature storage, which presents an obstacle to their application. In this paper, SBS modified asphalts with improved high-temperature storage stability were prepared by incorporating carbon black (CB) into the SBS compounds. The effect of CB on the high-temperature storage properties, dynamic rheology, mechanical properties (softening point, viscosity etc.) and the morphologies of the modified asphalts were studied. It was found that the ratio of SBS to CB in the compound had a great effect on the high-temperature storage behavior. The modified asphalts were stable when the ratio of SBS/CB was around 2. CB had almost no effect on the dynamic rheology or the mechanical properties of the modified asphalts. The improvement in high-temperature storage behavior could be caused by decreasing the density difference and improving the compatibility between SBS and asphalt.