Kinetically limited growth region

Statistical molecular fluctuations within a liquid can lead to the formation of microscopic vaporlike regions that have a radius greater than the critical one for bubble growth as given by Eq. 15.15. The formation of such nuclei and their subsequent growth is referred to as homogeneous nucleation. There have been two main approaches to the calculation of the temperature required for homogeneous nucleation. These are, respectively, determination of the thermodynamic limit and the kinetic limit. 

In any case, the region of accelerated aging must be limited by physical transitions (melting, glass transition), since the kinetic parameters undergo practically unpredictable discontinuous variations at these transitions, as illustrated by the example of oxidation (amide growth in an amide-cured epoxy) (Fig. 14.22). 

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