Comparative evaluation of the aging performance of hard asphalts using physical chemical relationships

ABSTRACTTwo 30# asphalts were prepared by solvent deasphalting of Oman residue and Saudi residue and their properties were evaluated. Results indicated that Oman 30# asphalt exhibited excellent high- and low-temperature performance and aging resistance performance compared to Saudi 30# asphalt. Based on n-pentane asphaltene content, the aging process of two 30# asphalts followed a first-order kinetic reaction equation. Oman 30# asphalt had higher activation energy and a lower reaction rate constant than Saudi 30# asphalt. Changes of compositions and molecular weight distribution of asphalts in aging process revealed that asphalt aging reaction mainly included dissociation and condensation. There existed a significant difference in compositions and chemical structures of 30# asphalts; high aromatic content, high asphalt colloidal stable index, and short alkyl side chains were beneficial to improvement of aging resistance performance.