Dynamic Material Functions and the Structure of Asphalts

Abstract

A simple model of the complex modulus, based on the general principles for a linear response function, is presented. The model represents a generalization of the Maxwell model and it is indicated that the model well describes a relatively broad group of regular and modified asphalts. A discrete spectrum of no more than 10 relaxation times is obtained for all the asphalts studied. The spectra of modified asphalts indicate the presence of several relaxation times that can be related to the interface interactions of the base asphalt and the polymers used. It is indicated that the phase angle of the complex modulus contains valuable information about the structure of asphalts. An attempt to use this information for calculations of the molecular mass distribution is presented. A possibility to characterize asphalts by the so-called pseudospectra is also discussed.