Poètes et poésies à l’âge des révolutions (1789-1820)

En s’interrogeant sur le statut du poète en Révolution, les réflexions rassemblées dans ce dossier s’emparent d’un objet qui a longtemps pâti d’une mauvaise réputation et dont la longue disgrâce historiographique n’a pris fin qu’assez récemment. La production poétique du tournant des Lumières a en effet souffert très tôt de nombreux préjugés. S’agissant des poètes révolutionnaires, la subordination à « un dogme social qui préexiste à leurs créations » leur a depuis longtemps valu un discrédit..

Poètes et poésies à l’âge des révolutions (1789-1820)

En s’interrogeant sur le statut du poète en Révolution, les réflexions rassemblées dans ce dossier s’emparent d’un objet qui a longtemps pâti d’une mauvaise réputation et dont la longue disgrâce historiographique n’a pris fin qu’assez récemment. La production poétique du tournant des Lumières a en effet souffert très tôt de nombreux préjugés. S’agissant des poètes révolutionnaires, la subordination à « un dogme social qui préexiste à leurs créations » leur a depuis longtemps valu un discrédit..

Physical and gas permeation properties of five-layer polyethylene film used as greenhouse roof

The effect of sand wind ageing simulation performed under different conditions for a five-layer film consisting of polyethylene, poly-vinyl-acetate and various additives has been investigated. The mechanical properties of the five-layer films after several treatments were evaluated, together with their surface morphology - analysed by using Fourier transform infrared and contact angle - and gas permeation properties. The experimental analysis indicated that these treatments had a significant influence on the surface of the film only. An attempt has been done to compare the properties of the five-layer films with the monolayer and tri-layer films with or without air bubble under similar conditions

Effect of the polar-nonpolar liquid mixtures on pervaporative behaviour of perfluorinated sulfonic membranes in lithium form

International audienc

Ab-initio study of cationic polymeric membranes in water and methanol

International audienc

Impact of water and thermal induced crystallizations in a PC/MXD6 multilayer film on barrier properties

A multilayer film composed of alternating layers of polycarbonate (PC) and poly(m-xylene adipamide) (MXD6) was elaborated by using an innovative multilayer coextrusion process. Quasi-continuous thin MXD6 layers (nanolayers) alternating with PC layers were successfully obtained. The PC/MXD6 multilayer film showed a confining effect of MXD6 exerted by PC layers leading to an improvement of barrier properties despite a low degree of crystallinity (X c < 10 wt%). In order to further improve the barrier performances, crystallization treatments induced by water and by heating were then applied on the multilayer film and allowed reaching around 30 wt% of crystallinity in MXD6 layers. To decouple crystallization and geometrical constraint effects on the barrier properties in the multilayer films, the two treatments were also applied on MXD6 films. Surprisingly, despite an increase of the degree of crystallinity from 6 to 26%, water crystallization did not permit to improve gas barrier performances of the MXD6 film nor into the PC/MXD6 multilayer film. On the other hand, thermal crystallization of MXD6 in the multilayer film seems to be a more efficient route to strongly decrease the gas and moisture permeability, up to 75% for nitrogen, 58% for oxygen, 84% for carbon dioxide and 43% for water

Poètes et poésie en révolution

International audienc

Vapour sorption and permeation behaviour of supported ionic liquid membranes: application for organic solvent/water separation

International audienc

Water molecular state in 1-hexylpyridinium hexafluorophosphate: Water mean cluster size as a function of water concentration

International audienc

The behaviour of wine aroma compounds related to structure and barrier properties of virgin, recycle and active PET membranes

Virgin PET, 100% recycled PET and PET containing an oxygen scavenger have been compared for their thermal properties and gas and aroma compound permeability. Thermal properties were slightly different between virgin and recycled PET, which exhibited the same degree of crystallinity but also strong heterogeneity in dispersion and size of crystals. However, glass transition was higher in the presence of oxygen scavenger because of its nature. Similar oxygen and carbon dioxide permeability were measured for virgin, recycled and PET with 1% of oxygen scavenger, whereas with 3% of oxygen scavenger gas barrier properties increased. Water barrier properties of PET were not influenced either by recycling or by the presence of oxygen scavenger and a plasticization effect was evidenced for all films. Concerning volatile organic compounds such as ethanol and aroma compounds, virgin PET was the best barrier. Permeability was strongly affected by the affinity of the compound for the material. Sorption of pure or diluted solution of ethanol induced changes in thermal properties with a slight decrease in Tg and a marked decrease of crystallinity. In contrast, the oxygen permeability after contact with the diluted solution of ethanol was increased, suggesting a reduction of free volume by sorption. Finally, the impact of film barrier properties on three aroma compounds of wine was evaluated and confirmed the inertness of PET concerning aroma compounds and the positive effect of active packaging