LOW TEMPERATURE CRACKING IN POLYMER MODIFIED BINDERS

One strategy used by asphalt material producers to enhance the performance of their products, and therefore the service life of highways, has been to add polymers to bitumen. One claim which has been made for polymer modified binders is that it improves resistance to low temperature cracking. The term "binder" is used in this paper to describe both bitumen (asphalt cement) and a combination of bitumen and polymer. A program of research to investigate the validity of this claim was initiated by British Petroleum, in conjunction with the research group at the University of Braunschweig. The second objective of the study was to attempt to determine what measurements can be made on the individual binders in order to indicate their relative performance in relation to low temperature cracking. These measurements could be of some use in framing binder specifications.