Rheology of Iraqi Asphalt Modified with SBS, Polyphosphoric Acid and Sulfur

Abstract

Polymer modified asphalts (PMA) became of greatinterest over the last years because there are closely related to industrialand constructional fields. To increase the elasticity of asphalt,styrene-butadiene-styrene (SBS) type polymers are used which are elastomericblock copolymers. Although the addition of SBS type block copolymers haseconomic limits and can show serious technical limitations, it is probably themost appropriate polymer for asphalt modification. The present work seeks toidentify the changes on the rheological and physical properties of SBS modifiedwith Dora asphalt. So it is the first study using Iraqi asphalt with styrene-butadiene-styrene.In this paper polyphosphoric acid PPA and sulfur were used to improve the hightemperature property and storage stability of SBS modified asphalt.PPA canimprove the high temperature performance of the SBS modified Dura asphalt evidentlybut declain the storage stability. Owing to the gelation of PPA, the phaseseparation of SBS becomes more serious.