Effects of Oil/Asphalt Emulsion Formulation on Particle Size and Stability

This investigation evaluated the factors of penetrant types, asphalt contents, and emulsifier contents on the particle sizes of emulsified penetrants, emulsified asphalt, and oil/asphalt emulsions in the emulsion formulation. The particle sizes of emulsions were obtained by laser particle size analyzer tests. The residues of emulsions obtained after the high-temperature evaporative technique were assessed through conventional binder tests such as softening point, penetration, and ductility tests. The storage stability of oil/asphalt emulsions was evaluated as well. Additionally, the molecular dynamics simulation was employed to study the interfacial interaction between materials in the emulsion system at the atomic scale. The results showed the great potential of using the commercial penetrants adopted for this study as alternatives to kerosene in emulsions with smaller particle sizes and better stability. The emulsifier content had significant effects on particle size and stability of emulsions. A higher emulsifier content had positive effects on decreasing the particle sizes and improving the stability of emulsions; however, it negatively affected the ductility of the emulsion residues. The particle sizes were noticed to be highly correlated to stability, emulsifier content, and interfacial formation energy of the emulsions.