Cooperative Relaxations in Condensed Macromolecular Systems. 1. A Model for Computer Simulation

A microscopic model of cooperative relaxations in condensed macromolecular systems is proposed. The mechanism suggested consists in collective replacement of molecular subsegments within closed loops of motion. The model is applied to computer simulations of chain motions on a lattice with all sites occupied. Examples of computer experiments based on melting of regular structures with linear and ring chains are shown. Final isotropic amorphous systems that are completely filled with ideal randomly coiled chains have been obtained. Chain lengths were varied between 16 and 1024 chain segments.