Steady-state permeation rates for pure COz and CH4 and the binary mixture through homogeneous dense polysulfone and polycarbonate membranes have been measured at 40°C and upstream pressures up to 26 atm. The pressure dependence of the mean permeability coefficients for COz and CH, for all of the sys
Sorption of gases in glassy polymers: A probabilistic model
✍ Scribed by Eric Favre; Pierre Schaetzel; Quang Trong Nguyen; Jean Néel
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 409 KB
- Volume
- 3
- Category
- Article
- ISSN
- 1022-1344
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The description of the sorption mechanism of gases in glassy in glassy polymers is of importance for membrane‐based gas separation processes as well as for packaging applications. Dual mode theory, postulating a Henry and Langmuir process to occur and leading to an equation with three adjustable parameters, is usually proposed in order to describe the isotherms. A simple mechanistic model, based on an unequal affinity between the gas molecules and the matrix regions occupied either by polymer or a previously sorbed gas molecule, is presented in this paper; in contrast to dual mode theory, this approach does not postulate the existence of microvoids in the glassy matrix. Integration leads to an equation with two adjustable parameters, which is shown to describe precisely already reported isotherms.
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