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Medical devices (MD) are often made of plasticized polyvinylchloride (PVC). However, plasticizers may leach out into infused solutions and expose the patients to a toxic risk. The aim of the present work is to fluorinate plasticized PVC tubular MDs to create a barrier layer on their internal surface, and to study the impact of such a chemical treatment on the migration of the plasticizers. Following fluorination by pure molecular fluorine, the physico-chemical characterization of these modified MDs was carried out using various spectroscopic and microscopic techniques or tensile tests, evidencing the formation of covalent C-F bonds on the surface of the treated samples without modification of their mechanical and optical properties. The migration of plasticizers from fluorinated MDs was assessed using gas chromatography coupled with mass spectrometry and was found considerably decreased in comparison with the pristine MDs. After 24 h, the amount of tri-octyltrimellitate plasticizer (TOTM) detected in migrates from fluorinated MDs was even lower than the limit of quantification. Complementary cytotoxicity assays were performed according to the ISO EN 10993-5 standard, showing that the new fluorinated material does not cause a cytotoxic effect on L929 cells.

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HYPOTHESIS: Development of a process yielding large-sized non-wettable coatings of immediate applicative interest seems feasible by associating a membrane spining technique with the artificial mimic of a bio-inspired strategy toward water repellency. Accordingly, the question that arises is how to design a multiscale textured and chemically-activated continuous film. EXPERIMENTS: A novel synergic combination of a processing technique and chemical treatment was developed in this purpose. Fluorinated nanocarbons were included in polyvinylpyrrolidone (PVP) microfibers via their addition in a precursor solution for electrospinning. The nanocomposites thus obtained were subsequently treated under gaseous molecular fluorine in mild conditions. FINDINGS: Owing to the reactivity of PVP with F2, both etching and functionalization occurred during such a post-treatment. The chemical modification undergone by PVP upon fluorination has been analyzed and a mechanistic approach proposed. An impressive dual texturing developed at the micro- and nanoscale thanks to the combined action of electrospinning, polymer etching and emergence of the nanofillers. This allowed a stable with time superhydrophobic coating-like film to be achieved.

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Chemistry in confined conditions is explored at the level of the interlayer space of multiwall carbon nanotubes. Starting from preliminary intercalated tubes, a ligand exchange reaction has been successfully conducted within the former Van der Waals gap, resulting in a final dispersion of heteroatomic particles, around 2 nm large and nearly homogeneous in size, on the outer surface of the tubes. Intercalated tubular carbon architectures thus prove to be interesting templates for a bottom-up preparation of chemically complex supported nanoparticles, with potential activities for versatile applications.

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A theoretical survey of the ability of fluorofullerene crystals to act as host lattices for intercalation chemistry is proposed on a thermochemical basis and from the assumption that complete charge transfer between the fluorocarbon network and an electropositive intercalant species should occur upon insertion. A nearly exhaustive examination is performed throughout the fluoro[60]fullerene family, describing the influence of the intercalated element considered, stoichiometry, structural type, and fluorine content on the potential stability of an intercalated phase. Decomposition of the latter into a metal fluoride is then discussed. When extended to a general scheme, emphasizing the role played by the number of carbon atoms in the initial cluster, the present model shows that stable fluorofulleride salts may be expected to form in some cases. A final insight into the solid state properties of this class of materials, combined with a widespread range of potential applications, is provided.