Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
In this Study, the surface energy was investigated for six penetration grade
70/100 bitumen binders. Wilhelmy Plate and the Sessile Drop were used to
determine the contact angles.
The purpose of this study was to compare the Wilhelmy Plate method with the
Sessile Drop method, and to compare the significance of Owens-Wendt model
with the significance of Acid Base model by correlating surface energy
components. Better R2 –values were found for surface energy components by
using the Owens-Wendt model than by using the Acid Base model. It was
concluded here that Owens-Wendt model is a better model for determining
surface energy components of bituminous binders than the Acid Base model
since bituminous binders have low energy surfaces.
For both instruments: When using Diiodomethane as a probe liquid the biggest
variations among the binders were observed. When using water as a probe
liquid the least variations among the binders were observed.
The advancing contact angles for water determined for these six bitumen
binders using the Wilhelmy plate method do not exceed the 90 degree by
much, suggesting that bitumen is not extremely hydrophobic.
The Sessile Drop method offers a faster and more convenient way to measure
the surface energy components of bitumen binders than the Wilhelmy Plate
2012. , 40 p.