The Morphology of Bitumen-SBS Blends by UV Microscopy

ABSTRACT The morphology of bitumen-SBS blends is studied using Epi-Fluorescence microscopy. Morphology is defined as the partition of polymer-rich and bitumen-rich phases. Existing sample preparation methods for microscopy on bitumen are compared and the obtained morphologies are shown. In a second part, differences in morphology are related to differences in rheological behavior. The morphological properties strongly depend on the temperature, where a sample is taken, upon the cooling rate and upon isothermal annealing periods. During isothermal storage the morphology can undergo major changes. The so-called bulk morphology, which is obtained from a freeze-fractured surface, is different from the morphology seen on the surface which has been in contact with air or with silicon.