Abstract
Volume dilatometric, dynamic mechanical and dielectric measurements and creep test are made on seven kinds of asphalt differing in the extent how far the blowing is processed. With the in-crease of asphaltene content, the glass transition point shifts to a higher temperature and the in-tensity of glass transition becomes weaker, and, at the same time, both the viscosity and retardation time of elastic deformation undergo a conspicuous increase, while the equilibrium elastic compliance remains almost unaffected. Such behavior is interpreted as indicating that the viscoelasticity of asphalt is essentially due to Brownian motion of maltene molecules, on which asphaltene molecules have a suppressing effect.
Both the free carrier of electric charge and the electric dipole increase in number with increas-ing asphaltene content. The dipoles are believed to be mostly ester groups as proved by infrared absorption.
