Asphalt, as a complex high molecular hydrocarbon, exhibits typical elastic-visco-plastic properties under certain temperature and load, and will age under high temperature and ultraviolet irradiation. Therefore, the main purpose of using modified asphalt equipment to add asphalt modifiers is to improve the road performance of asphalt mixtures at high temperatures, reduce deformation at high temperatures, improve its resistance to rutting, fatigue, and aging, as well as resistance to low-temperature cracking or increase fatigue resistance at low temperatures, so that it meets the requirements of traffic conditions during the design period. In addition, the use of modified asphalt equipment can also improve the adhesion between asphalt and mineral materials and the antioxidant capacity of the binder. One of the main functions of modified asphalt is to enhance the ability of asphalt mixtures to resist deformation at high temperatures and reduce temperature sensitivity, while having no adverse effects on the characteristics of asphalt or asphalt mixtures at other temperatures. From the research and application of polymer modified asphalt in China, it can be seen that whether a polymer can be used as a modifier usually meets the following conditions:
(1) Good resistance to high temperature deformation;
(2) Enhanced resistance to low temperature cracking and reflective cracking;
(3) The modified asphalt has good adhesion and water damage resistance to aggregates;
(4) Has resistance to long-term aging and a long service life;
(5) Good compatibility with base asphalt;
(6) Can resist decomposition at the mixing temperature of asphalt mixture;
(7) Modified asphalt is easy to process and can be mass-produced;
(8) Can always maintain the original excellent performance during use;
(9) Economically reasonable, without significantly increasing the project cost.
