Gas separation of 6FDA-6FpDA membranes Effect of the solvent on polymer surfaces and permselectivity
Gas separation of 6FDA-6FpDA membranes Effect of the solvent on polymer surfaces and permselectivity
- Journal of Membrane Science, 293(1-2), p.22-28, 2007 .
The aim of this work has been to analyze how different solvents used in the manufacture of gas separation membranes, based on 6FDA-6FpDA, influence permeability and selectivity. It has been shown that a low boiling point and/or a repulsive interaction between the solvent and the polymer increase both selectivity and permeability for O2/N2 and, specially, for CO2/CH4 gas pairs. These results have been explained in terms of fractional free volume and intersegmental mobility. In particular it has been shown that good solubility of the polymer results in a high glass transition temperature and planar surface as characterised by the fractal dimension of the resulting membranes, obtained from AFM analysis.
FLUORINATED POLYIMIDES
GAS SEPARATION
FRACTIONAL FREE VOLUME
FRACTAL DIMENSION
SOLUBILITY PARAMETER
The aim of this work has been to analyze how different solvents used in the manufacture of gas separation membranes, based on 6FDA-6FpDA, influence permeability and selectivity. It has been shown that a low boiling point and/or a repulsive interaction between the solvent and the polymer increase both selectivity and permeability for O2/N2 and, specially, for CO2/CH4 gas pairs. These results have been explained in terms of fractional free volume and intersegmental mobility. In particular it has been shown that good solubility of the polymer results in a high glass transition temperature and planar surface as characterised by the fractal dimension of the resulting membranes, obtained from AFM analysis.
FLUORINATED POLYIMIDES
GAS SEPARATION
FRACTIONAL FREE VOLUME
FRACTAL DIMENSION
SOLUBILITY PARAMETER