Manufacturing process optimization and multi-mechanism stability regulation of high-performance emulsified asphalt

The commonly used Styrene-Butadiene-Styrene (SBS) emulsified asphalt suffered from low viscosity grade and poor storage stability. This paper established a full-dimensional closed framework encompassing precursor asphalt selection, preparation parameter optimization, oil-water stability mechanism elucidation, and macro-micro parameter correlation quantification for high-viscosity and high-elasticity emulsified asphalt (HVE-EA). Grey relational analysis was adopted to clarify the selection of modified asphalt, while single-factor experiments and response surface methodology (RSM) were employed to optimize the coupled preparation parameters of HVE-EA. Furthermore, interfacial tension, particle size distribution, and Zeta potential tests were performed to illustrate the influence mechanism of HVE-EA stability. The results indicated that at the SBS dosage was 9%, the grey relational grade corresponding to the optimal target value reached 0.9413, with the dynamic viscosity exceeding 200000 Pa·s. The RSM was employed to minimize the deterioration of 1d/5d storage stability under the action of coupled influencing factors, confirming that stability reached 0.35% and 2.95% when the emulsifier content, stabilizer content, and soap solution pH were 3.217%, 0.156%, and 2.014, respectively. Through the synergistic regulation of reduced interfacial thermal force, refined particle size, and electrostatic repulsion, the surface tension (SFT), interfacial tension (IFT), average particle size, and Zeta potential of HVE-EA were optimized to 40.12 mN/m, 2.626 mN/m, 3.62 μm, and 98.61 mv, respectively. Notably, the average particle size regulated by soap solution pH and the Zeta potential influenced by emulsifier exhibited a strong negative correlation. This paper provides an elegant system for regulating HVE-EA from microcosmic parameters to macroscopic stability.