J. Phys. IV France
Volume 03, Numéro C4, Septembre 19934th International Workshop on Positron and Positronium Chemistry
|Page(s)||C4-223 - C4-224|
J. Phys. IV France 03 (1993) C4-223-C4-224
Thermal and pressure properties of amorphous polymers: relation to probe spectroscopyR. SIMHA
Department of Macromolecular Science, Case Western Reserve University, Cleveland, Ohio 44 106-7202, U.S.A.
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.
© EDP Sciences 1993