A polymer molecule in solution is treated as a porous sphere with a spherically symmetric permeability distribution. Solvent motion in and around this sphere is described by the Debije- Brinkman equation (Navier-Stokes equation and Darcy equation combined). The model allows a straightforward...

We present a macroscopic derivation of the Debije-Brinkman equation for the flow of a fluid through a polymer coil. By using an exact relation between the sedimentation coefficient and the permeability it is found that the permeability of the coil is strongly dependent on the nature of the...