Aspects of self-diffusion of solvent in polymer-low molecular weight substance system

Abstract

On the assumption of the independent behaviour of the holes necessary for diffusion it is shown that in the polymer-low molecular weight substance system at T>Tg + (80-100) where Tg is the glass transition point of the system, the temperature dependence of the self-diffusion coefficient D of the solvent may be described by an equation of the Arrhenius type with the activation energy constant ED, which was also observed experimentally. It was established that fall in the self-diffusion coefficient with rise in the content of the polymer in the system is due to kinematic restrictions on the movement of small molecules. Rise in ED with fall in the content of the solvent is due, in the main, to increase in the energy of formation of the hole. © 1984