Preparation technology of modified asphalt
SBSrubber powderHDPE composite
1. School of Materials Science and Engineering, Chang′an University, Xi′an, Shaanxi 710061, China; 2. Engineering Research Center of Transportation Materials of Ministry of Education, Chang′an University, Xi′an, Shaanxi 710064, China
Abstract:Using SK90# matrix asphalt, the orthogonal experiment with 6 test variables was adopted to prepare composite modifying asphalt. The determined technical indexes were analyzed by gray relational analysis to obtain the optimum preparation process parameters of composite modifying asphalt. The results show that the softening point and 5 ℃ ductility of asphalt are significantly improved by SBSrubber powderHDPE, and the elastic recovery rate of the twentysecond group sample reaches 60% with good elasticity. The optimum technological parameters for preparing SBSrubber powderHDPE modifying asphalt are determined by gray relational analysis with modifier SBS content of 5.0%, modifier powder content of 20.0%, modifier HDPE of 4.5%, shear rate of 4 500 r·min-1, shear time of 45 min and shear temperature of 170 ℃. SBS and HDPE are intertwined with each other under the action of high temperature shearing to form threedimensional network structure with polymer as dispersion medium and asphalt as dispersed phase, and the overall performance of composite modifying asphalt is improved.