Direct and continuous methodological approach to study the ageing of fossil organic material by infrared microspectrometry imaging: application to polymer modified bitumen Original Research Article

A new simulation method was developed for studying the ageing of polymer modified bitumens (PmBs). An ageing cell specially was designed and fitted to a Fourier transform infrared (FTIR) microscope to continually and directly study the oxidation of PmB by FTIR microscopy imaging. The method was applied to a styrene–butadiene–styrene (SBS) modified bitumen. This PmB features a two-phase structure with polymer-rich areas along with polymer poor regions. Changes in the chemical properties were observed during ageing. This structural and functional evolution was monitored in both phases simultaneously to determine the kinetics of appearance and disappearance of chemical species. The method also allows the study of ageing by kinetic mapping. Moreover, this methodology allows the analysis of PmB samples without destroying their internal equilibrium. This paper presents some of the possibilities of this new ageing cell.