Abstract
The review deals with the characteristic features of the molecular motion of flexible chain macromolecules and oligomers associated with the multisegmental nature of the chain and topological limitations. The dependence of the self-diffusion coefficients of chain molecules in polymer melts and solutions, including a weakly cross-linked gel, is analysed. Attention is concentrated on data for self-diffusion where there is a change not only in the molecular weight (MW) of the diffusing molecule but also in the molecular weight of the macromolecules surrounding the specified molecule. Both model ideas and approaches based on the scaling theory, including the concept of the curvature of the trajectories of the "reptation tube", are used for the theoretical analysis. The "inhomogeneity" of the segmental mobility in the chain has made it possible to describe specific features of the behaviour of oligomers. The dependence of the self-diffusion coefficient on the MW of the chain and the matrix and on the concentration in the region of dilute, moderately concentrated, and concentrated solutions and melts has also been described quantitatively.
The bibliography includes 69 references.