| Abstract
| - A new molecular thermodynamic model is developed of the glass transition temperatures (Tg) of binarypolymer−salt complexes by combining configurational entropy theory with Guggenheim's form of the Debye−Hückel theory. The interactions between the polymer chains and the salt as well as those between cations andanions are accounted for by this model. The predictions of this extended configurational entropy theory arecompared with the Tg values of poly(2-ethyl-2-oxazoline) (POZ) complexed with AgBF4, AgClO4, AgCF3SO3, and AgNO3 at various compositions, as obtained by differential scanning calorimetry (DSC). The modelaccurately predicts the experimental Tg values even at high concentrations of silver salt (i.e., up to a moleratio of [Ag]/[CO] = 1/1), where the deviation of the simple configurational entropy theory from experimentaldata is large. Moreover, the maximum in the glass transition temperature, i.e., the increase in Tg with saltconcentration at low salt concentrations but its decrease at high salt concentrations, is explicable with thismodel.
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