Two-phase diffusion: Diffusion through polymers and polymer blends

Abstract The application of two-phase conductivity theory to diffusion, in particular to diffusion in polymers and polymer blends, is discussed. The permeability is seen as the property which, e.g. Maxwell's equation may describe, not the diffusion coefficient . The “energy of activation” of diffusion may not be a useful concept for such systems. Measurements of permeability of He, A, O 2 and paraxylene through blends of polyethylene and poly-propylene are shown to be consistent with Maxwell's results.