Evaluation of adhesion of asphalt binders using wicking experiments

The objective of this study was to develop a methodology to evaluate the adhesion of liquids to porous by solids using wetting/wicking experiments. The surface area of porous materials significantly increases compared with that of their solid analogs. Hence, pores play an important role in the adhesion of resins and binders to solids. The authors developed an experimental protocol allowing one to evaluate the work of adhesion, a characteristic thermodynamic parameter of the liquid/porous solid pair. It is shown that for the determination of the work of adhesion, one needs to know the pore size distribution, the wicking constant of the wetting liquid and the surface tension of the liquid. Asphalt binders and different rocks were studied to illustrate the methodology.