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

Abstract

Polymer modified asphalts (PMA) became of great interest over the last years because there are closely related to industrial and constructional fields. To increase the elasticity of asphalt, styrene-butadiene-styrene (SBS) type polymers are used which are elastomeric block copolymers. Although the addition of SBS type block copolymers has economic limits and can show serious technical limitations, it is probably the most appropriate polymer for asphalt modification. The present work seeks to identify the changes on the rheological and physical properties of SBS modified with 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 high temperature property and storage stability of SBS modified asphalt.PPA can improve the high temperature performance of the SBS modified Dura asphalt evidently but declain the storage stability. Owing to the gelation of PPA, the phase separation of SBS becomes more serious.

Keywords

• Polyphosphoric acid,Sulfur

References

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