Page 59 - 《橡塑技术与装备》英文版2025年12月

MATERIALS AND FORMULATIONS

(a) Softening point; (b) Penetration; (c) Ductility; (d) Elastic recovery
Figure 3 Conventional physical properties of PMA and SMA at different desulfurization temperatures

softening the asphalt, and increasing its penetration. Within desulfurization of CR increases, the crosslinking density of
a certain range of desulfurization degree, as the degree of the prepared DCR continuously decreases. Rubber with a high
desulfurization increases, the dispersibility and compatibility crosslinking density can better maintain its elastic structure in
of CR in asphalt improve, and CR's improvement effect asphalt, contributing more to the elastic recovery of asphalt.
on the flexibility and deformability of asphalt is enhanced, When the crosslinking density decreases, the elasticity of the
gradually increasing the ductility. Ductility is used to evaluate rubber phase weakens, leading to a decrease in the overall
the plasticity of asphalt. DCR disperses uniformly in asphalt, elastic recovery ability of asphalt. The crosslinking density
enhancing the cohesion and flexibility of asphalt, allowing it to of vulcanized rubber powder is closely related to its swelling
withstand greater deformation without breaking when stretched capacity. The higher the crosslinking density, the stronger its
by external forces, and thus increasing ductility. ability to absorb light components in asphalt. As the degree
As the degree of desulfurization of rubber powder of desulfurization of rubber powder increases, its ability to
increases, the elastic recovery of asphalt tends to decrease. absorb light components in asphalt weakens. The swelling
The rubber molecular chains in CR form a stable cross-linked effect of light components in asphalt on the rubber phase
network structure through vulcanization, giving the rubber decreases, and the rubber phase cannot swell sufficiently to
powder good elasticity. However, the desulfurization process fully exert its elastic properties, thereby affecting the elastic
reduces the crosslinking density of rubber. As the degree of recovery of asphalt. The desulfurization reaction causes the

Vol.51，2025 ·53·