Investigation on preparation and rheological properties of grafted organic long-chain carbonitride (CNDC) modified asphalt

Abstract

In order to improve the high temperature and low temperature properties of asphalt and its ultraviolet (UV) aging resistance, a type of modifier grafted organic long-chain carbonitride (CNDC) was prepared. The modifier was characterized using various methods, such as Fourier transform infrared spectroscopy, scanning electron microscope and thermogravimetric analysis. The performance of CNDC modified asphalt was analyzed through conventional item tests and dynamic shear rheological tests. In addition, the dispersion characteristics of CNDC in asphalt was analyzed by optical microscope. The test results showed that the organic long-chain was grafted onto the carbonitride surface successfully and the thermal stability of CNDC was good. The dynamic shear rheological tests results demonstrated that the addition of CNDC could improve the high temperature performance of asphalt. The low temperature crack resistance of asphalt was best when the CNDC content is 3%. Furthermore, the fatigue resistance can be improved by 30% when the CNDC content was 1%. The UV aging resistance of asphalt could be improved when the content of CNDC was less than 3%. The optical microscopy test results showed that the CNDC particles did not agglomerate when the content was less than 3%. The results of the softening point difference indicated that the storage stability of the modified asphalt was good. In this study, CNDC modified asphalt had reached a balance between high and low temperature performance, which was to improve the rutting resistance of asphalt without reducing the low temperature performance. Moreover, the addition of CDNC could improve the UV aging resistance of asphalt. This study can give some help for the research of inorganic material asphalt modifiers.