Premium
Studies with thin membranes. III. Measurement of water permeabilities of parlodion membranes formed by the dip technique
Author(s) -
Lakshminarayanaiah N.
Publication year - 1967
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1967.070110913
Subject(s) - membrane , permeation , permeability (electromagnetism) , materials science , chemistry , chemical engineering , analytical chemistry (journal) , chromatography , biochemistry , engineering
Thin Parlodion membranes whose preparation and electrochemical properties have already been described are used to study permeation of water through them. All the membranes allowed water to go through them when subjected to gradients of mechanical pressure or chemical potential. Thicker membranes were less permeable to water than thinner membranes. The total water flow observed under the influence of an applied pressure was analyzed in terms of an existing theory due to Ticknor and found inadequate to describe the flow in thicker membranes containing low quantities of water, whereas the flow in thinner membranes of moderate water content was found to be made up of both viscous and diffusional components. On the contrary, analysis of both the total and isotopic diffusional flows from the standpoint of another theory due to Mauro showed that all membranes gave flows which were composed of both diffusional and viscous components, the proportion of the former in the total flow increasing with increasing thickness of the membrane. The permeability data have been used to derive values for both the average radius of membrane pores and the total number of such pores present in different membranes.