ABSTRACT
Polyurethane is a relatively new type of binder for pavements. In this paper, curing and adhesion characteristics of two single-component polyurethane (PU) binders were studied. And chemical composi-tional, pull-out and shear analyses were performed to evaluate the curing performance of two PU binders. Meanwhile, the strength of PU were also adopted to represent adhesion characteristics (the binding capacity to the aggregate). With the increase of natural curing conditions, the results show that the isocyanate index of PU-I and PU-II decreases , while the Urea Index have the opposite trend. Both the isocyanate index and urea index of PU are stable after 4 days natural curing, indicating that PU are nearly fully cured after 4 days curing. As for pull-off and shear strength, PU-I and PU-II have better binding capacity to stone and rubber. Mean-while, the binding capacity of stone-PU–rubber system is the worst.
