Model pores of molecular dimension. The preparation and characterization of track-etched membranes.

Extremely uniform pores of near molecular dimension can be formed by the irradiation-etching technique first demonstrated by Price and Walker. The technique has now been developed to the stage where it can be used to fabricate model membranes for examining the various steric, hydrodynamic, and electrodynamic phenomena encountered in transport through molecular-size pores. Methods for preparing and characterizing membranes with pores as small as 25 A (radius) are described in this paper. Results on pore size determination via Knudsen gas flow and electrolyte conduction are compared. Pore wall modification by monolayer deposition is also discussed.