Optimization of mixing time for polymer modified asphalt

Asphalt pavement made with neat binder is not sufficient to resist heavy traffic loads as well as harsh environmental condition. Therefore, there is a need to modify the binder with polymers in order to improve its properties. From literature, it was indicated that various blending process parameters, namely, blade shape, temperature, shear rate and mixing time influenced the properties of the produced polymer modified asphalt. In this study, the influence of mixing time on six different types of polymer with 60/70 asphalt binder was focused. The polymers were blended with asphalt binder and inspected at 30 minutes intervals during the mixing process. Then, all the samples were tested through Dynamic Shear Rheometer at 58C, 64C and 70C. It was shown that the complex modulus (G∗) values at these temperature levels for all polymers modified asphalt indicated proper particles dispersion within the binder. The optimal blending time, which produces the best rheological properties of all modified asphalt is 30 minutes except for asphalt modified with Lucolast7010 and Anglomak2144, which is 60 minutes. In conclusion, mixing time has significant influence on the particle distribution of polymer within the binder to ensure the quality of asphalt-polymer blend.</p