Research On The Rheological Properties And Low Temperature Properties Of DIBCH Plasticizer Modified Asphalt

Plasticizer is a kind of polymer material additive,which is widely used in rubber and plastic products.It can enhance the flexibility and tensile properties without changing the basic chemical properties of the substance.The plasticizers used nowadays are basically ester compounds,which do not react with polymers in any way.After plasticizer is added,the elongation and flexibility of the polymer are improved,and the embrittlement temperature is decreased.As for asphalt materials,with the increase of flexibility and embrittlement temperature,asphalt binder can adapt to lower temperature and has better low temperature crack resistance.In order to improve the crack resistance of asphalt binder at low temperature,a new environmental plasticizer——diisobutyl cyclohexanedicarboxylate(DIBCH)was used to modify the performance of SK90.Dynamic shear rheological test and bending beam rheological test of SK90 and four DIBCH modified asphalts with different content were carried out respectively.The improvement effect of DIBCH on the performance of asphalt binder was analyzed.The low temperature performance of DIBCH asphalt mixture was studied by low temperature trabecular bending test.The effect of DIBCH on low temperature performance of SK90 was compared with that of rubber powder and SBS modified material to determine the improvement degree of DIBCH on low temperature performance of asphalt.Finally,the microstructure and chemical composition of DIBCH modified asphalt were studied by Fourier transform infrared spectroscopy,and the modification mechanism of DIBCH on SK90 asphalt was studied.The conclusions are as follows:(1)The dynamic shear rheological test data show that the linear viscoelastic range of DIBCH modified asphalt is larger than that of SK90,the larger the content of DIBCH,the larger the linear viscoelastic range of asphalt,and the degree of homogeneity of DIBCH modified asphalt is also greater than that of SK90;(2)after adding DIBCH,the rutting factor of asphalt decreases and the phase angle increases,which indicates that DIBCH makes asphalt more homogeneous.The high temperature performance of SK90 decreases with the increase of medium viscosity,but DIBCH does not change the high temperature grade of SK90.(3)After RTFOT aging,the complex modulus and rutting factor of SK90 and DIBCH modified asphalt increase continuously,which indicates that the high temperature rutting resistance of RTFOT asphalt is improved.(4)The recovery rate of DIBCH modified asphalt decreases,the irreversible creep compliance increases,and the creep recovery ability decreases.(5)DIBCH plasticizer significantly enhanced the low temperature crack resistance of SK90,and the improvement degree was better than rubber powder and SBS modified asphalt.(6)RTFOT/PAV aging has less effect on DIBCH modified asphalt than SK90.After aging,DIBCH asphalt still has better low temperature performance and has a higher low temperature grade than SK90.(7)There is no chemical reaction between DIBCH plasticizer and SK90,only physical blending.However,the addition of DIBCH into SK90 increases the content of light components,which further verifies the improvement of low temperature performance of asphalt...