تعيين تغييرات توزيع وزن مولكولي قير با تابع ريولوژيكي دلتا

Determination of Bitumen Molecular-weight Distribution via its Delta Rheological Function

In this research molecular weight distribution (MWD) of the base bitumen and the corresponding changes in the control sample were calculated using the phase angle experimental rheological data and the model developed by Stastna et al. via calculated relaxation times. According to the calculated MWDs it is observable that bitumen constituents undergo both an increase and a decrease in molecular weight or in the size of molecular clusters during mixing at high temperature. Since this type of calculation was not carried out for the base and control bitumen at the same time, the observed changes in molecular weight as new finding should be taken in consideration in bitumen production and processing. Due to lack of any solvent, this method is considered as a non-destructive test for analyzing bitumen structure and could be used conveniently in controlling the quality and structure of bitumen during processing and in service aging as well as structural and property changes.