A NOVEL TECHNIQUE FOR THE CHARACTERIZATION OF ASYMMETRIC MEMBRANES BYPERMOPOROMETRY

A modified technique for the characterization of membranes by liquid d isplacement permoporometry has been described. The modifications allow an estimate of the shape of a pore in an asymmetric membrane to be ma de. The erroneous nature of the conclusions that would be drawn if per moporometric data, obtained with a membrane with asymmetric pores, is treated under the assumption of right cylindricity has been demonstrat ed by means of such an analysis done on a hypothetical asymmetric memb rane. While there is little error in the estimation of pore radii, the pore numbers are grossly overpredicted by a right cylindrical pore mo del for the membrane. The extent of this overprediction increases with the asymmetry of the membrane.