Research On Performance And Crossblend Mechanism Of Nanometer ZnO/SBS Modified Asphalt

As a new material of the modified asphalt, nanometer particle modifier has becomea new research direction. Basing one the researching conditions of the modified asphaltand the development and applying study of the nanometer both in and out of the word,the article firstly takes ZnO and SBS as modifier to discuss the functions in theprinciples of the modified asphalt, which is placing an important role in studying,developing and applying in modified asphalt of nanometer.Choosing three kinds of matrix asphalt, two linear structure SBS and nanometerZnO, some relating experiments of modified asphalt were done. Proceeding from thetechnique, three kinds of methods were proposed combined with the right condition inthe lab, which were high speed shearing method, substrate method, mechanical agitation.Compared with the performances of modified asphalt with the three methods, substratemethod can give full play to nanometer ZnO and distribute SBS uniformly. The hightemperature performance, the low temperature performance, anti-aging performance isall well improved. Finally the substrate method is adopted and the facts of dose,temperature and time etc to the performances of modified asphalt are studied.Fixed the dose of SBS (5%) and chose five doses of nanometer ZnO to modifiedthe matrix asphalt. The conventional and unconventional testing methods were adoptedto evaluate the ZnO/SBS modified asphalt. The result shows that with the developmentof doses of ZnO, the high temperature performance, the low temperature performanceand the anti-aging performance of modified asphalt are more and more built up.Especially 5℃ductility was up to 90cm. With the increasing of nanometer ZnO, thesoftening point is some decreased, and its high temperature performance varies verylittle. The performance reaches its best form when the doses of ZnO and SBS are all5%.Selected Caltex asphalt as the matrix asphalt, the nanometer ZnO modified asphalt,SBS modified asphalt and nanometer ZnO/SBS modified asphalt were made to test theirperformance. It can be seen that the high temperature performance, low temperatureperformance and its mixtures performance of modified asphalt are well improved. The order from bad to good is matrix asphalt, nanometer ZnO modified asphalt,SBSmodified asphalt, and nanometer ZnO/SBS modified asphalt.Fluorescent microscope and SEM were used to analyze the microstructure ofnanometer ZnO/SBS modified asphalt. IR and NMR were selected to study the blendcross mechanism of nanometer ZnO/SBS modified asphalt. It shoes that the preparationof nanometer ZnO/SBS modified asphalt is a complicated chemical and physicalprocess. The reaction between SBS and asphalt is physical and the reaction betweennanometer ZnO and asphalt is chemical.