Assembly of nanocomposite PEBAX membranes: A complementary study of affinity and clusterization phenomena

The behaviourofablock co-poly(ether/amide)80PTMO/PA12(PEBAX)membraneblendedwithan amphiphilicfiller, N-ethyl-o/p-toluenesulphonamide(KET),wasstudiedbothexperimentallyand theoreticallyinordertoidentifytheaffinity,themiscibilityandtheeffectivedistributionand arrangementofKETmoleculesandthemechanismcontrollingwaterinteractionsondifferentlength scales,frommacrotonano.Bothmethodshavealsobeenusedtoestablishtheroleofmolecular rearrangementandclusterizationphenomenaofmodifiersinpackedmembranes,andtorelatethisto the macroscopicaffinitybehaviour.ThecompatibilitybetweenKETandPEBAXandthepresenceof nanoclustersofKETinsidethematrixhavebeenstudiedatmolecularlevelthroughmodelling, calorimetryandinfraredspectroscopyanalyses.Agoodmiscibilityhasbeenobservedupto50wt% of modifiercontentbutwithdiscrepancieswhenKETisat70wt%,confirmingasaturationof hydrophilicsitesofthefiller,resultinginareducedaffinityofthemembranestopolarpenetrant.An integratedexperimental-theoreticalapproachhasprovidedamoredetailedinvestigationofthree- componentcomplexsystems,inwhichthemacroscopicpropertiesandmorphologiesaredetermined by interactionsinthenano-scalerange,thusresultinginareciprocalvalidationandusefulcorrelations betweenMDandexperimentalanalysis.