NEW DIRECT OBSERVATIONS OF ASPHALTS AND ASPHALT BINDERS BY SCANNING ELECTRON-MICROSCOPY AND ATOMIC-FORCE MICROSCOPY

Observations made using AFM and SEM have been combined in order to stu dy the structure of asphalts. Fluorescence microscopy was used to aid in understanding the structural changes occurring when polymer is adde d to the asphalts. With the atomic force microscope we are able to stu dy the structure of the asphalts without any pre-preparation. Despite very low resolution, our study revealed a network of asphaltene molecu les with regard to asphalt gel. The same result is obtained by SEM obs ervation but with a much better resolution. SEM observation, however, needs an adequate preparation method. In the presence of polymer we ob served a rearrangement of the initial asphaltene association which lea ds to the assumption that polymer can aggregate the asphaltene phase.