Research On Property Of SBR Modified Asphalt And Mixture Impacted By DTDM

Polymer-modified asphalt has become a relatively mature pavement material for high standard road in recent years.It is made to improve the asphalt through mixing the matrix asphalt with polymer and stirring them.However,the polymer modified asphalt made only by stirring and shearing can not well show the polymer's good modification effect due to the consistency problem of polymer and asphalt.In order to better show the polymer's modification effect,get the polymer modified asphalt with excellent high and low temperature performance,this paper adopts the reactive blending fabrication method to make SBR modified asphalt,using the star-like SBR powder as the main modifier to modify the matrix asphalt Panjin 90~#and then make styrene-butadiene rubber polymer and asphalt in acidic or alkaline groups to set off a chemical reaction under certain condition through bringing in the cross-linking agent DTDM(4,4`-dithiodimorpholine).Strengthening the consistency of polymer and matrix asphalt through scattering,swelling,adsorption,crosslinking and so on to form the uniform and steady two phase continuous mesh structure of polymer modified asphalt and then comparing and analyzing the polymer modified asphalt and mixture with different mixing amounts of butadiene styrene rubber and DTDM.Results show that the adding of styrene-butadiene rubber makes the high temperature performance of asphalt be slightly improved and the low temperature performance be improved a lot;The added volume of styrene-butadiene rubber should not be too large,4%is proper.If there went no cross-linking reaction,the consistency of SBR with 4%added volume and asphalt would be worse and the segregation phenomenon would easily happen.The consistency problem of modifier and asphalt in SBR modified asphalt made by reactive blending has been improved a lot so the SBR modified asphalt can keep its stable system under high temperature,which satisfy the requirements of manufacture and use.After adding the DTDM,the dynamic stability of SBR modified asphalt will be increased by about 45%,TSR will be increased by 10%,and the breaking strain of the modified asphalt after cross-linking will be 1.4 times larger than those without cross-linking.It shows that cross-linking reaction after adding DTDM will also improve the pavement performance of the SBR modified asphalt mixture.