Characterization of Asphalt Binders Based on Chemical and Physical Properties

Abstract

Abstract The chemical compositions and physical properties of unmodified and polymer-modified asphalts were studied using high-performance gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), thermal mechanical analysis (TMA), and differential scanning calorimetry (DSC). Two viscosity-based asphalt grades (AC-5 and AC-10) and two polymers, namely, styrene-butadiene-styrene (SBS) and styrene-ethylene-butylene-styrene (SEBS) were used to modifiy asphalt in this study. The combination of GPC and FTIR was found to be an excellent approach for fingerprinting and quality control of polymers and asphalt binders. The rheological properties of asphalt binders were determined to be good characteristics for determining the optimum polymer concentrations for effective modification. The DSC results indicated that different asphalt grades have different levels of polar associations as detected from changes in enthalpy. Polymer modification alters these associations. TMA was a fast method for determining the highest possible service temperature of the pavement.