Activation energy for the glass

As a function of MW Activation energy for the glass transition See Rets. 62,64... 

Fig. 4.1 Arrhenius plots for ionic conductivity, (a) General behaviour for ionically conducting glasses. At room temperature, the most conductive (Li or Ag ) have the lowest activation energy. For the less conductive glasses (Cs or mixed alkali glasses) the activation energy is around 1 eV. (b) Experimental data for Li conducting glasses (Souquet and Kone, 1986).

Note that calculated energies have been substituted for the more normal free energies of Marcus theory. Equation (2) predicts a low 7.2 kcalmoPM activation energy for the 1 -+ 2. The experimental work in Freon glasses did not reveal the existence of 1, although recent work has shown that it does have a finite lifetime in solution and that the estimated rearrangement barrier is 4.8 kcalmo] [12],... 

Telegina et al. 72> showed that the activation energy for the viscous flow of a polyester oligomer filled with glass microspheres is 46.9 kJ/mol, while that of an epoxy oligomer is 78.3 kJ/mol. They also established the important fact that the addition of microspheres to an oligomer composition does not change the temperature viscosity coefficient. This means that the viscosity of a mixture with microspheres can be controlled, if the temperature dependence of the viscosity of the binder is known. 

An apparent activation energy for the thermo-coloring was estimated to be V35 Real/mol, according to the method described previously (3). This value is almost the same as that of the other glasses reported by Abe et al. (3). 

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