Linear response of regular asphalts to external harmonic fields

Dielectric permittivity and mechanical complex compliance of regular asphal ts, at T = 323 K, are studied. Both the loss compliance and the loss of per mittivity functions can be decomposed into two parts. The first part repres ents the viscous deformation and the ohmic conductivity, respectively. The second part then describes a ''pure" response of the material to external h armonic fields. By this decomposition one can observe a relatively strong t ransition of regular asphalts into their relaxed state. A simple fractional model of the response function can be applied to both mechanical and diele ctric transitions. (C) 1999 The Society of Rheology. [S0148-6055(99)00803-2 ].