LOCAL DYNAMICS AND GLASS-TRANSITION

The dynamics of polymer chains in the bulk state rue discussed at thre e different temperature scales: (i) Well above the glass transition te mperature where the basic step of motion is the rotameric transition o f bonds. In this regime, the dynamics may conveniently be analyzed by the rotational isomeric state model. (ii) In the vicinity of glass tra nsition where friction forces from the environment dominate. In this r egime, the dynamics may be modeled according to the cooperative kinema tics model. (iii) Well below glass transition. Here, an analogy with a native protein is made, and the mean-squared fluctuations are analyze d by adopting the Gaussian Network Model, which recently proved succes sful in describing fluctuations in native proteins.