Although the use of polymeric additives has been widely accepted as a promising strategy to improve
broad spectrum of pavement deficiencies, aging-induced mechanisms of polymer-modified asphalt binders
and mixtures still have critical aspects that should be studied to a comprehensive extent. The primary
objective of this paper is to advance the understanding of aging effect on the properties of
polymer-modified asphalt binders and mixtures. In this study, six different polymeric products were of
specific interest: styrene-butadiene-styrene (SBS), polypropylene (PP), styrene-acrylonitrile (SAN),
high-density polyethylene (HDPE), polycarbonate (PC), and acrylonitrile-butadiene-styrene (ABS), each
was applied at rates of 2% and 5% (by the wt. of asphalt binder) to prepare polymer-modified binders
and mixtures. The prepared binders passed thin film oven test (TFOT), while the mixtures were subjected
to normal and 16 h production aging. The compositional analysis of asphalt binders was discussed based
on the elemental analysis tests while the penetration, ring and ball, and rotational viscosity tests were
further studied to evaluate the physical properties. The asphalt mixtures were evaluated based on a series
of engineering performance-based properties using indirect tensile strength (ITS), moisture susceptibility,
uniaxial static creep-recovery, resilient modulus, and diametral fatigue tests. The fatigue tests were
conducted without and with rest period so as to provide insight into the healing potential of different
modified mixtures. The results showed that the aging increased the carbon component in all blends;
however mixed results were attained regarding hydrogen, sulphur, and nitrogen. No obvious trends were
ascertained for carbon, hydrogen, nitrogen, and sulphur due to polymer modification. Aging induced
effects on polymer-modified binders and mixtures are highly dependent on the polymer type and modification
level. Polymer modification had positive influence on ITS, creep strain and recovery ratio, resilient
modulus, resistance to moisture damage, and fatigue life. Fatigue tests with rest period proved
that the polymer-modified mixtures have higher tendency to heal compared to the unmodified mixtures,
which resulted in an improvement in the fatigue performance of the mixtures. Except for the fatigue life,
the aging of polymer-modified asphalt mixtures had no detrimental effect on the studied mechanistic
properties.