partially draining

https://doi.org/10.1351/goldbook.P04414
An adjective describing a chain macromolecule that behaves in a hydrodynamic field as though the solvent within the domain of the macromolecule were progressively more immobilized with respect to the macromolecule in the direction from its outer fringes inward. A freely draining macromolecule and a non-draining macromolecule are two extremes of the concept of a partially draining macromolecule.
Source:
Purple Book, 1st ed., p. 61 (http://old.iupac.org/publications/books/author/metanomski.html)