Study on design and optimization of novelty asphalt rejuvenator composition based on crystal nucleus dispersion theory

This paper developed a new rejuvenator based on the Crystal Nucleus Dispersion Theory and evaluated the aging performance of the new rejuvenator. The component conditioner was selected based on the chemical composition and colloidal stability index of the asphalt. The association degree, colloidal particle size, particle size distribution and conductivity of asphaltene were considered to select the compatibilizers. The wax crystal dispersant was chosen based on the distribution and fractal dimension of wax crystal. Orthogonal test was used to determine the composition of asphalt rejuvenate agent and a new asphalt rejuvenate agent was prepared. The aging resistance of new rejuvenate agent was evaluated through the quality change and viscosity ratio after the thin film oven test (TFOT). The results indicate that the catalytic cracking slurry A, which was rich in aromatic, improves the colloidal stability of aged asphalt significantly. Dodecyl benzene sulfonic acid, which has acidic groups of high activity, reduces the association degree and disperses asphaltene aggregates into smaller units. The wax crystal dispersant can disperse coarse wax crystals into fine and uniform wax crystal particles. The fractal dimension of wax crystal increases from 1.08 to 3.26 and have a good exponential relationship with the low temperature ductility of asphalt. The mass loss and viscosity ratio of new rejuvenate agent were 1.12% and 1.28%, which were lower than the present rejuvenate agent. The aging resistance of the new rejuvenate agent was better than present rejuvenators. (C) 2019 Elsevier Ltd. All rights reserved.