Paper Number
PO126 

Session
Poster Session

Title
Microstructure of SBS modified asphalt binder by small-angle neutron scattering

Presentation Date and Time
October 17, 2018 (Wednesday) 6:30

Track / Room
Poster Session / Woodway II/III

Authors (Click on name to view author profile)

  1. Shan, Liyan (Harbin Institute of Technology, School of Transportation Science and Engineering)
  2. Xie, Ru (University of Delaware)
  3. Wagner, Norman J. (University of Delaware)
  4. Liu, Yun (National Institute of Standards and Technology, Center for Neutron Research)

Author and Affiliation Lines (in printed abstract book)
Liyan Shan1, Ru Xie2, Norman J. Wagner3, and Yun Liu4
1School of Transportation Science and Engineering, Harbin Institute of Technology, Harbin, China; 2University of Delaware, Newark, DE; 3University of Delaware, Newark, DE; 4Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD

Speaker / Presenter 
Shan, Liyan

Text of Abstract
The microstructure of asphalt binders is thought to have a significant effect on the performance of binders used in roadway construction, however, there are limited studies of their nanoscale to microscale structure. Here, small angle neutron scattering (SANS) is used to study the microstructure of neat asphalt binder, SBS polymers and SBS modified asphalt binder. The results show that the micelle in asphalt binders was plated-shape and the size was larger than 1800 Å. Both the intensity curve and the rheology results showed that SBS modified asphalt has a phase transition temperature around 110°C, while the SBS micelles swell and loose contrast above this temperature. The thermal reversibility of this phenomenon proves that the SBS modified mechanism is a physical modification of the microstructure as proposed in the colloidal model of asphalt. Modeling of the SANS spectra shows that both SBS polymer and SBS in asphalt binder have a lamellar structure surrounding by a shell. The results of this paper are useful to analyze the relationship between microstructure of asphalt binder and pavement performance and develop a new type of modified asphalt binder.