Activation energy soft segment glass transition

The apparent activation energies ( ACT) of the dynamic mechanical transitions can be calculated from the temperature at the maximum in the loss modulus T(G"max) as a function of frequency. A typical Arrhenius plot (see Fig. 2) of the apparent activation energy of the soft segment glass transition for 73 series polymers yields E/ ct values of approximately 75 + 5 kcal/mole (314 kJ/mole) over a frequency range of 2 decades. 

Figure 2. The apparent activation energy of the soft segment glass transition for Halthane 73-15 is determined from the slope of a plot of In f vs. 1 /T(G"max).

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