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ECOLE DOCTORALE « Mécanique, Energétique, Génie Civil, Procédés » Vous êtes cordialement invités à la soutenance de la thèse de Altun, Veysi Dec 6-2016 at 13 :30 KU Leuven, Onderwijs & Navorsing, O&N II Herestraat 49, 3000 Leuven, Belgium SOLVENT STABLE UV AND EB CROSS-LINKED POLYSULFONE-BASED MEMBRANES Résumé The importance of membrane technology as a separation technique has increased rapidly over the past decades thanks to its broad range of applications. The expanding market brings along the requirement of advanced polymeric materials, which show resistance towards swelling and plasticization in gas separation (GS) and towards harsh solvents and extreme pH conditions in solvent resistant nanofiltration (SRNF). At this stage, cross-linking has emerged as a promising technology to overcome these issues. Chemical cross-linking is one of the most commonly used techniques and is based on a chemical reaction between a polymer (e.g. polyimide) and a cross-linker (e.g. diamine or diol). However, for polymers which do not contain chemically reactive groups in their backbone, such as polysulfones (PSU), this technique is not feasible. Additionally, chemical cross-linking involves several processing steps and causes harmful waste streams, triggering the quest for a generally applicable, fast and green curing technique. Two new curing techniques, namely ultraviolet (UV) and electron beam (EB) curing, were explored in this thesis, in order to obtain chemically and thermally stable membranes, hence being attractive for SRNF applications. Asymmetric membranes, composed of a semi-interpenetrating polymer network (SIPN), were prepared via non-solvent induced phase separation (NIPS). PSU was chosen as polymer because of its robust thermal and mechanical properties, photosensitivity and lack of reactive groups. Cross-linked membranes with SIPN structure were obtained via UV and EB-curing. The influence of cross-linker functionality, radiation dose and polymer/cross-linker ratio on the EB-curing efficiency was investigated. The best type of cross-linker and its optimum concentration under optimum EB-dose were determined. To optimize the separation performance of EB and UV-cured PSU membranes, the effect of phase inversion parameters, including polymer concentration, evaporation time prior to immersion and co-solvent/solvent ratio, was explored. Solvent stable asymmetric PSU membranes were thus developed by two simple, environmentally friendly and highly effective methods. The performance and enhanced chemical resistance of the cured membranes show high potential for implementing both cross-linking procedures in adequate industrial applications after further optimization. Mots-Clés: SRNF, PSU membranes, phase inversion, EB cross-linking, UV cross-linking Etablissement d’inscription : KU Leuven (Belgium) Université Toulouse 3 Paul Sabatier (France) University of Twente (the Netherlands) Composition du Jury: 1. Vankelecom, Ivo, Prof. Dr. (co-directrice de thèse) 2. Remigy, Jean-Christophe, Dr. (co-directrice de thèse) 3. Benes, Nieck, Prof. Dr. (co-directeur de thèse) 4. Aimar, Pierre, Dr. 5. Koeckelberghs, Guy, Prof. Dr. 6. Kemperman, Antione, Dr. 7. Rabiller-Baudry, Murielle, Prof. Dr. (rapporteur) 8. Aerts, Peter, Dr. (rapporteur)