Macroscopic description of solvent diffusion in polymeric materials

Diffusion of small molecules in polymeric materials is accompanied by a variety of processes including swelling, changes of state, development and eventual release of macroscopic elastic stresses, and onset of fracture, Providing a consistent theoretical description capable of interpreting and predicting the behavior of these systems has proven challenging The present article highlights recent developments towards this goal in a number of areas, including swelling of crosslinked polymeric networks (rubbers and gels), and diffusion accompanied by plasticization, that is, by a change to the rubbery state, in glassy polymers. A brief account of the main unresolved issues is also given.