Influence of temperature, pressure and connectivity on the dynamics of a glass-forming system investigated by dielectric spectroscopy

A comparative study is reported on the dynamics of a glass-forming system w hen the glass transition is approached through different paths: cooling, co mpression, and polymerization. In particular, the influence of temperature, pressure and connectivity on the dynamics has been investigated by dielect ric spectroscopy. A phenomenological description of the behavior of the die lectric response shows the existence of both differences and deep similarit ies between the change of some dielectric parameters during a polymerizatio n reaction and during the temperature or pressure changes. A unified readin g of our experimental results can be given in the framework of the Adam-Gib bs theory.