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La présente étude a été consacrée à l'étude du potentiel du PDMS pour l'élaboration d'... more La présente étude a été consacrée à l'étude du potentiel du PDMS pour l'élaboration d'un procédé de séparation membranaire à sélectivité variable et contrôlée. La nanofiltration se base une théorie relativement jeune. Les mécanismes impliqués dans les performances des membranes sont encore sujet à controverse au vu des données de la littérature. La caractérisation du gonflement solvo-dépendant du polymère, ainsi que de ses propriétés de compressibilité à l'état gonflé, ont permis de relier directement les propriétés de perméation et de tamisage moléculaire d'une membrane de PDMS à son état physico-chimique. L'étude de l'influence des paramètres opératoires a dans un premier temps permis d'apporter des éléments de compréhension significatifs concernant les propriétés de perméation résultant de la variabilité de l'agencement structural et géométrique du réseau polymérique. Degré de gonflement, compressibilité de la membrane lorsque soumise à la pres...
La presente etude a ete consacree a l'etude du potentiel du PDMS pour l'elaboration d'... more La presente etude a ete consacree a l'etude du potentiel du PDMS pour l'elaboration d'un procede de separation membranaire a selectivite variable et controlee. La nanofiltration se base une theorie relativement jeune. Les mecanismes impliques dans les performances des membranes sont encore sujet a controverse au vu des donnees de la litterature. La caracterisation du gonflement solvo-dependant du polymere, ainsi que de ses proprietes de compressibilite a l'etat gonfle, ont permis de relier directement les proprietes de permeation et de tamisage moleculaire d'une membrane de PDMS a son etat physico-chimique. L'etude de l'influence des parametres operatoires a dans un premier temps permis d'apporter des elements de comprehension significatifs concernant les proprietes de permeation resultant de la variabilite de l'agencement structural et geometrique du reseau polymerique. Degre de gonflement, compressibilite de la membrane lorsque soumise a la pres...
Polymer Testing, 2014
ABSTRACT This study aims to better understand the permeation properties of polydimethylsiloxane (... more ABSTRACT This study aims to better understand the permeation properties of polydimethylsiloxane (PDMS) membranes. The compressibility and nanofiltration fluxes were measured for swollen PDMS films using several solvents at applied pressures ranging from 5 to 50 bar. The degree of swelling varied according to the solvent and the pressure applied. To show the correlation between the behaviour of the swollen PDMS under pressure and its permeation performance, the thickness reduction of the membrane was mimicked using uniaxial compression tests. The evolution of the nanofiltration flux as a function of the transmembrane pressure proved to be non-linear. Linearization was achieved by taking into account both the swelling and the thickness reduction previously measured, confirming that these phenomena may have occurred during the nanofiltration experiments. Moreover, the solvents' viscosity and affinity for the polymer were confirmed to have a great influence on their ability to permeate the membrane. Finally, employing the most commonly used models, a study of transport through the membrane led to the conclusion that the experimental results were in agreement with the hydraulic theory of transport.
Journal of Applied Polymer Science, 2014
ABSTRACTIn this study, retention experiments were performed to characterize the variable sieving ... more ABSTRACTIn this study, retention experiments were performed to characterize the variable sieving properties of a poly(dimethylsiloxane) (PDMS) membrane in relation with operating parameters. The swelling, transmembrane pressure, and temperature are all known to impact the physicochemical properties and morphology of PDMS polymer and were therefore varied for the purposes of our retention experiments which assessed them with the homologous series of polyethylene glycols (PEGs; 200–1500 g mol−1). The objectives were twofold—first, to evaluate the capacity to induce a targeted molecular weight cutoff (MWCO) by selecting appropriate filtration conditions and second to better understand the mechanisms involved during solvent‐resistant nanofiltration with PDMS. The selected solvents or solvent/solvent mixtures used throughout this study were found to induce swelling ratios of 1.16 (ethanol/ethyl acetate: 25/75), 1.26 (ethyl acetate), 1.33 (ethyl acetate/toluene: 50/50), and 1.41 (toluene)...
La présente étude a été consacrée à l'étude du potentiel du PDMS pour l'élaboration d'... more La présente étude a été consacrée à l'étude du potentiel du PDMS pour l'élaboration d'un procédé de séparation membranaire à sélectivité variable et contrôlée. La nanofiltration se base une théorie relativement jeune. Les mécanismes impliqués dans les performances des membranes sont encore sujet à controverse au vu des données de la littérature. La caractérisation du gonflement solvo-dépendant du polymère, ainsi que de ses propriétés de compressibilité à l'état gonflé, ont permis de relier directement les propriétés de perméation et de tamisage moléculaire d'une membrane de PDMS à son état physico-chimique. L'étude de l'influence des paramètres opératoires a dans un premier temps permis d'apporter des éléments de compréhension significatifs concernant les propriétés de perméation résultant de la variabilité de l'agencement structural et géométrique du réseau polymérique. Degré de gonflement, compressibilité de la membrane lorsque soumise à la pres...
La presente etude a ete consacree a l'etude du potentiel du PDMS pour l'elaboration d'... more La presente etude a ete consacree a l'etude du potentiel du PDMS pour l'elaboration d'un procede de separation membranaire a selectivite variable et controlee. La nanofiltration se base une theorie relativement jeune. Les mecanismes impliques dans les performances des membranes sont encore sujet a controverse au vu des donnees de la litterature. La caracterisation du gonflement solvo-dependant du polymere, ainsi que de ses proprietes de compressibilite a l'etat gonfle, ont permis de relier directement les proprietes de permeation et de tamisage moleculaire d'une membrane de PDMS a son etat physico-chimique. L'etude de l'influence des parametres operatoires a dans un premier temps permis d'apporter des elements de comprehension significatifs concernant les proprietes de permeation resultant de la variabilite de l'agencement structural et geometrique du reseau polymerique. Degre de gonflement, compressibilite de la membrane lorsque soumise a la pres...
Polymer Testing, 2014
ABSTRACT This study aims to better understand the permeation properties of polydimethylsiloxane (... more ABSTRACT This study aims to better understand the permeation properties of polydimethylsiloxane (PDMS) membranes. The compressibility and nanofiltration fluxes were measured for swollen PDMS films using several solvents at applied pressures ranging from 5 to 50 bar. The degree of swelling varied according to the solvent and the pressure applied. To show the correlation between the behaviour of the swollen PDMS under pressure and its permeation performance, the thickness reduction of the membrane was mimicked using uniaxial compression tests. The evolution of the nanofiltration flux as a function of the transmembrane pressure proved to be non-linear. Linearization was achieved by taking into account both the swelling and the thickness reduction previously measured, confirming that these phenomena may have occurred during the nanofiltration experiments. Moreover, the solvents' viscosity and affinity for the polymer were confirmed to have a great influence on their ability to permeate the membrane. Finally, employing the most commonly used models, a study of transport through the membrane led to the conclusion that the experimental results were in agreement with the hydraulic theory of transport.
Journal of Applied Polymer Science, 2014
ABSTRACTIn this study, retention experiments were performed to characterize the variable sieving ... more ABSTRACTIn this study, retention experiments were performed to characterize the variable sieving properties of a poly(dimethylsiloxane) (PDMS) membrane in relation with operating parameters. The swelling, transmembrane pressure, and temperature are all known to impact the physicochemical properties and morphology of PDMS polymer and were therefore varied for the purposes of our retention experiments which assessed them with the homologous series of polyethylene glycols (PEGs; 200–1500 g mol−1). The objectives were twofold—first, to evaluate the capacity to induce a targeted molecular weight cutoff (MWCO) by selecting appropriate filtration conditions and second to better understand the mechanisms involved during solvent‐resistant nanofiltration with PDMS. The selected solvents or solvent/solvent mixtures used throughout this study were found to induce swelling ratios of 1.16 (ethanol/ethyl acetate: 25/75), 1.26 (ethyl acetate), 1.33 (ethyl acetate/toluene: 50/50), and 1.41 (toluene)...