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H. Grothe, F. Handle, M. Harir, J. Füssl, A. Koyun, D. Großegger, N. Hertkorn, L. Eberhardsteiner, B. Hofko, M. Hospodka, R. Blab, P. Schmitt-Kopplin:
"Tracking Ageing of Bitumen and its SARA Fractions Using High-Field FT-ICR Mass Spectrometry";
Talk: 53rd Petersen Asphalt Research Conference, Jackson, Wyoming, USA; 2016-07-18 - 2016-07-21.

Asphalt binder is a widely used material, but its ageing behavior is only understood at a macroscopic level as hardening and embrittlement over time. To assess asphalt binder ageing behavior on the long run, the pressure ageing vessel (PAV) testing procedure was developed. However, this procedure has not been understood on a molecular level yet. Here, a binder sample and its SARA fractions were investigated in comparison with their aged samples to study changes of their chemical compositions using high-field FT-ICR-MS. The effect of ageing was followed using aromaticity equivalent, double bond equivalent and van Krevelen plots. It was found that ageing induces reduction of condensed aromatic compounds to alicyclic and openchain
aliphatic compounds, while small aromatic compounds have been found to be relatively stable. Abundant alterations were detected in unaged binder. These changes can be assigned to resins and asphaltenes. Overall, alterations of highly condensed compounds were found to be ageing in a related way. Furthermore, CHO, CHNO and CHOS molecular compositions were more susceptible to oxygenation in aromatics, resins and asphaltenes as compared to saturates. In addition, molecular changes in asphaltenes showed significant difference from classical assessment with high content of condensed aromatic compounds.