Entropy, glass transition temperature relaxation parameters

The short time mode corresponds to the glass transition. In polymers like polystyrene, a narrow distribution is observed. Ihe width of the distribution reflects the width of the distribution of the order parameter it is increased after mechanical orientation by addition of a dopant or additive, or under special glass forming conditions (hydrostatic pressure or rheomolding). The distributed relaxation times obey a compensation law, they are reduced to a single time at the compensation temperature T. The departure of from the glass transition is related to the kinetic aspect of the transition. Thermodynamic models are based on the linear relationship between the activation enthalpy and the activation entropy. 

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