Isocyanate modified asphalt samples were got by adding quantitative isocyanate into the base asphalt. Isocyanate and nano particles composite modified asphalt samples were produced by adding quantitative isocyanate and three different kinds of inorganic nanoparticles (Silicon dioxide, Titanium dioxide, Zinc oxide) into the base asphalt respectively. Isocyanate modified asphalt, isocyanate and nanoparticles composite modified asphalt were characterized by taking physical tests, SEM, fluorescence microscopy, TG and FTIR tests, which demonstrated that the high and low temperature performance of isocyanate and nano particles composite modified asphalt had been improved effectively. From the microscopic view, the modification of the base asphalt was very significant. Results also indicated that the temperature sensitivity of composite modified asphalt had been decreased. Meanwhile, the thermal stability had been improved when compared with the base asphalt and isocyanate modified asphalt.
Xiong Xu,Jianying Yu,Lihui Xue,Bianyang He,Wei Du,Huang Zhang,Ying Li
The excellent comprehensive performance of SBS modified bitumen (SMB), during a long-term thermo- and photo-oxidative exposure, will fail to satisfy the pavement requirement. In this paper, the synergistic effect of 4,4′-diphenylmethane diisocyanate (MDI) and 1,4-butanediol diglycidyl ether (BUDGE) on the molecular weight of aged SBS was firstly studied, through a simulation, to confirm whether a new polymer structure can be obtained. Then, the reactive rejuvenating system containing MDI, BUDGE and bituminous composition returning agent (MDI-BUDGEs) was applied in the rejuvenation of aged SMB. The results show that the rebuilt molecular structure of aged SBS can be obtained with the combination of MDI and BUDGE. Meanwhile, MDI-BUDGEs can improve the low-temperature ductility and inhibit the sharp fall of the softening point of aged SMB, while decrease the viscosity-temperature response at 120–165 °C. Also, MDI-BUDGEs can contribute for increasing the viscous component, improving the fatigue resistance and remaining the high-temperature performance grade of aged SMB, and moreover, decrease the limited elastic modulus and the elastic-plasticity transition rate to avoid the occurrence of the brittle failure within a small strain range.
危险品化学品经营许可证（带存储）