Thermal and pressure properties of amorphous polymers: relation to probe spectroscopy

Abstract
We discuss the elements of a statistical thermodynamic theory of an equilibrium melt and its corresponding quasi-equilibrium glass. It involves a lattice model with a fraction h of vacancies as a measure of structural disorder. In the equilibrium melt the function h (V, T) is derived by a minimization of the configurational free energy. In the glass of specified formation history it is obtained from the experimental equation of state. The interpretation of this function as a free volume quantitiy in the frame of the lattice model results in important connections betwen thermodynamic and kinetic processes. In the present context the theory establishes correlations between the properties of the matrix and the characteristics of the o-positronium species.