Local Dynamics and Glass Transition

The dynamics of polymer chains in the bulk state are discussed at three different temperature scales: (i) Well above the glass transition temperature where the basic step of motion is the rotameric transition of bonds. In this regime, the dynamics may conveniently be analyzed by the rotational isomeric state model. (ii) In the vicinity of glass transition where friction forces from the environment dominate. In this regime, the dynamics may be modeled according to the cooperative kinematics model. (iii) Well below glass transition. Here, an analogy with a native protein is made, and the mean-squared fluctuations are analyzed by adopting the Gaussian Network Model, which recently proved successful in describing fluctuations in native proteins.