Nanoporous polymer fibres are currently attracting increasing interest due to their unique characteristics. Increased specific surface area, improved mechanical properties and improved cellular growth are amongst the advantages that set porous fibres as ideal candidates in applications like catalysis, separation and tissue engineering. This work explores the single step production of porous poly(ε-caprolactone) (PCL) fibres through combinative electrospinning and Non-solvent Induced Phase Separation (NIPS) technique. Theoretical models, based on three different contact models (Hertzian, DMT, JKR), correlating the fibrous network specific surface area to material properties (density, surface tension, Young s modulus, Poisson s ratio) and network physical properties (density) and geometrical characteristics (fibre radius, fibre aspect ratio, network thickness) were developed in order to calculate the surface area increase caused by pore induction. Experimental results proved that a specific surface area increase of up to 56% could be achieved, compared to networks composed of smooth surfaced fibres. The good solvent effect on electrospun fibre surface morphology and size was examined through experimental investigation of four different good solvent (chloroform, dichloromethane, tetrahydrofuran and formic acid) based solutions at various good/poor solvent ratios. Chloroform was proven to be the most suitable solvent for good /poor solvent ratios varying from 75-90% v/v, whereas alternative mechanisms leading to different fibre morphologies were identified, interpreted and discussed. Evaporation rate of the good solvent was identified as the key parameter of the process. Second order polynomial equations, derived from the experimental data, correlating the feed solution physical parameters (viscosity, conductivity, surface tension) to the fibre average diameter produced were developed and validated. Response surface methodology was implemented for the design and conduction of electrospinning experiments on a 12.5 % w/v Chloroform/DMSO solution 90/10 % v/v in order to determine the individual process parameters (spinning distance, applied voltage, solution flow rate) effect in fibre surface morphology and size. The increase in any of these parameters results in increase of both the fibre size and the tendency for pore generation, whereas applied voltage was the parameter with the strongest effect. Findings from this thesis expand the knowledge about both phenomena occurring during the production process and end product properties, and can be used for the production of controlled morphology and size porous poly(ε-caprolactone) (PCL) fibres.

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Les stents urétéraux et les sondes de néphrostomie sont constitués de silicone ou de polyuréthane thermoplastique (TPU). Afin de limiter les risques infectieux lors de leur implantation, une modification topographique par création de pores permettrait de limiter l’adhésion des bactéries et de former des réservoirs pour une libération in situ de substances antiinfectieuses. Ce travail vise à préparer des surfaces en polymère ayant un motif poreux tubulaire ordonné. Une réplication en deux temps à partir de surfaces ordonnées poreuses d’oxyde d’aluminium (PAAO) préparées par 2 méthodes (double anodisation douce et double anodisation dure/douce) a été mise en œuvre pour reproduire le motif initial sur des surfaces en silicone et TPU. Pour le moule intermédiaire trois matériaux ont été testés (acrylonitrile butadiène styrène, polystyrène et résine polyacrylate). Les surfaces ont toutes été caractérisées par des techniques microscopiques et spectroscopiques. Les surfaces en PAAO préparées par double anodisation douce possédaient des pores d’environ 50 nm de diamètre et 100 nm de profondeur, alors que celles obtenues après mise au point de la méthode dure/douce étaient de taille supérieure, d’environ 125 nm de diamètre et ayant des profondeurs de quelques centaines de nanomètres. La surface du moule intermédiaire est constituée de picots. Une adhésion latérale de ceux-ci a été observée pour certaines conditions. La meilleure réplication du motif a été obtenue pour le TPU. Les surfaces ainsi obtenues pourront être utilisées et optimisées lors de l'étude ultérieure de l'adhésion du biofilm. / Ureteral stents and nephrostomy catheters are made of silicone or thermoplastic polyurethane (TPU). A topographical modification creating an ordered porous surface could limit the infectious risks during their implantation, by reducing bacterial adhesion and creating a loading platform from which anti-infectious compounds could be released.In this work, a two-steps replication method was used to create ordered porous polymer surfaces (silicone or TPU) using porous anodic aluminium oxide (PAAO) as master template. The PAAO surfaces were prepared by double mild or double hard/mild anodization. Three intermediate mould materials were tested (acrylonitrile butadiene styrene, polystyrene, polyacrylate resin). The polymer material (silicone or TPU) was then moulded onto the intermediate mould surfaces that possessed freestanding pillar arrays, to imprint pores. The obtained surfaces were characterized by microscopic and spectroscopic methods. The initial PAAO surfaces prepared by double mild anodization possessed pores of about 50 nm diameter and 100 nm depth, whereas those prepared after development of the double hard/mild anodization method were bigger, of about 125 nm diameter and several hundred nanometers deep. The intermediate mould structure possessed freestanding arrays, but instabilities (lateral adhesion) were noted for certain conditions. The best pattern replication was observed for TPU. In conclusion, these novel porous polymeric surfaces could be optimized and tested for an anti-biofilm effect.