Linear free energy relationship in the diffusion of gases through polymer films

Abstract
The general correlation between ΔH/T and log D0 in the diffusion of gases through polymers is discussed in terms of a linear free energy relationship. It is shown that the diffusion constant D can be expressed as log D = kα + constant, where k is a parameter characteristic of the diffusing gas and α is a parameter characteristic of the polymer. The relationships between structural characteristics of gases and polymers and the respective parameters k and α are discussed. The possible application of similar linear free energy relationships for the purpose of expressing the permeability constant (P) and the solubility coefficient (S) is also suggested.
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