Enhanced Performance of LDPE/SBS Blend Modified Asphalt through Dynamic Vulcanization

A blend of a Low-Density Polyethylene (LDPE) and a Styrene-Butadiene-Styrene triblock copolymer (SBS) was mixed with an asphalt, and a storage-stable modified asphalt was prepared by dynamic vulcanization. The vulcanization characteristics of this LDPE/SBS blend-modified asphalt were studied using a strain-controlled rheometer. The vulcanization of the SBS in the blend-modified asphalt resulted in a marked increase in the torque. In addition, the physical properties of the LDPE/SBS blend-modified asphalt containing even a small quantity of sulfur were improved compared to the modified asphalt without sulfur. The storage stability of the LDPE/SBS blend-modified asphalt was also improved by the addition of sulfur. The rheological properties of the LDPE/SBS blend-modified asphalt before and after adding sulfur were characterized using a dynamic shear rheometer and a rotational viscometer.