Authors: Kevinilo P. Marquez and Rheo B. Lamorena-Lim
The study aims to: (1) determine the relationship between different heating conditions and the resulting compositional profile of asphalt fumes, and (2) create a baseline study about the relevant chemical properties and composition of the locally-used asphalt. The method involves the use of Headspace Gas Chromatography – Mass Spectroscopy (GC-MS) for qualitative and quantitative analysis of fume composition. Findings suggest that in spite of the high variability between asphalt source and composition, there exist a strong and direct relationship between fume composition and Penetration Grade (PG). Lower PG means greater composition of either high MW components or components that exhibit high molecular interaction (hydrogen bonding and/or dipolar interaction). Also, there is a trend observed between increasing incubation (heating) time and fume composition. The relative amounts of each component of the grade 10 samples show larger changes than that of the grade 65 samples. It means that the inner structure of the Grade 10 samples contains more maltenes and asphaltenes than that of the Grade 65 samples, which has shown a relatively consistent composition even at higher heating times. This method will provide far more information about the chemistry, structure and properties of asphalt materials than conventional physical property assessments like viscosity and hardness.
Keywords: Asphalt; Gas Chromatography-Mass Spectrometry ; Penetration Grade; Chemical Composition