MECHANISM OF SUPERSLOW RELAXATIONAL PROCESSES IN NONDILUTE LINEAR-POLYMERS

On the basis of the Gaussian subchains model in the unimolecular approximation the dynamics of the particular subchain in the polymer melt with engagements has been studied. The environment of a macromolecule is considered as a viscoelastic medium. The characteristic times-and scales in the system have been determined. The mechanism of superslow relaxational processes demonstrated in various phenomena (diffusion, viscoelasticity, optical anisotropy) is explained. Their relation with the stress relaxation in the polymer sample and dependence on the concentration and MM are shown. The role of the macromolecule ends has been studied. The obtained results are compared with those obtained by the de Gennes, Doi and Edwards approach. The anisotropy of the macromolecule mobility is shown to be a result of the used motion equation.