Activation energy theories, polymer glass

We have so far discussed two types of theories, those based on the site model, and thosebased on the WLF equation and its ramifications, which deal with time-temperature equivalence. The site model theories predict constant activation energies and are more applicable to relaxation transitions originating from localised chain motions, whereas the WLF equation theories deal with the glass transition behaviour in amorphous polymers. 

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