An electrolytic double-cell system was used to determine the variation in the diffusivity of through membranes at 280 to 333K. The diffusivities determined were described by:

D (cm2/s) = 3.86 x 10-3 exp[-5.5(kcal/mol)/RT]

T.Ishikawa, R.B.McLellan: Acta Metallurgica, 1986, 34[9], 1825-32