The physical properties and the dynamic viscoelasticity of the modified asphalt were investigated and the following results were obtained.
(1) The asphalt modified by the catalytic semiblowing has the gel type colloid structure as expressed by As/P, where As is the asphaltene content and P is the state of peptization of asphaltene micelle. Therefore, the modified asphalt becomes less temperature-susceptible and has a high softening point and a low brittle point. The relaxation spectrum takes high value for the wide range of relaxation time. It indicates that the modified asphalt has more elastic property than the straight asphalt.
(2) The asphalt modified by adding polymer shows low temperature susceptibility. The relaxation spectrum gets higher value for the wide range of relaxation time as the asphalt has a lower brittle point.
