https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Mon, 08 Jun 2026 14:43:32 GMT 2026-06-08T14:43:32Z http://hdl.handle.net/10985/10359 Industrial vegetable oil by-products increase the ductility of polylactide RUELLAN, Alexandre; GUINAULT, Alain; SOLLOGOUB, Cyrille; CHOLLET, Guillaume; AIT-MADA, Aziza; DUCRUET, Violette; DOMENEK, Sandra The use of industrial by-products of the vegetable oil industry as ductility increasing additives of polylactide (PLA) was investigated. Vegetable oil deodorization condensates were melt-blended by twin-screw extrusion up to a max- imum inclusion quantity of 20 wt% without preliminary purification. Sample films were obtained by single screw cast extrusion. Compounded PLA films featured largely improved ductility in tensile testing with an elongation at break up to 180%. The glass transition temperature remained higher than room temperature. The native mixture of molecules, which composed the deodorization condensates, had superior performance compared to a synthetic mixture of main compounds. The investigation of the correlation between composition of the additives and the ductility of the PLA blends by Principal Component Analysis showed synergy in property improvement between fatty acids having a melting point below and beyond the room temperature. Furthermore, a compatibilizing effect of molecules present in the native mixture was evi- denced. Oil deodorization condensates, which are a price competitive by-product of the vegetable oil industry, are therefore a very promising biobased and biodegradable additive for improving the ductility of PLA. Thu, 01 Jan 2015 00:00:00 GMT http://hdl.handle.net/10985/10359 2015-01-01T00:00:00Z RUELLAN, Alexandre GUINAULT, Alain SOLLOGOUB, Cyrille CHOLLET, Guillaume AIT-MADA, Aziza DUCRUET, Violette DOMENEK, Sandra The use of industrial by-products of the vegetable oil industry as ductility increasing additives of polylactide (PLA) was investigated. Vegetable oil deodorization condensates were melt-blended by twin-screw extrusion up to a max- imum inclusion quantity of 20 wt% without preliminary purification. Sample films were obtained by single screw cast extrusion. Compounded PLA films featured largely improved ductility in tensile testing with an elongation at break up to 180%. The glass transition temperature remained higher than room temperature. The native mixture of molecules, which composed the deodorization condensates, had superior performance compared to a synthetic mixture of main compounds. The investigation of the correlation between composition of the additives and the ductility of the PLA blends by Principal Component Analysis showed synergy in property improvement between fatty acids having a melting point below and beyond the room temperature. Furthermore, a compatibilizing effect of molecules present in the native mixture was evi- denced. Oil deodorization condensates, which are a price competitive by-product of the vegetable oil industry, are therefore a very promising biobased and biodegradable additive for improving the ductility of PLA. http://hdl.handle.net/10985/7995 Ion exchange membranes based upon crosslinked sulfonated polyethersulfone for electrochemical applications MABROUK, Walid; OGIER, Lionel; VIDAL, Serge; SOLLOGOUB, Cyrille; MATOUSSI, F.; FAUVARQUE, J.F Synthesis and characterization of new ion exchange membranes made from chlorosulfonated polyethersul- fone (SO2Cl-PES) crosslinked by polyaminated crosslinking reagents have been performed. Two examples are described: one crosslinked by hexane diamine, the other by amino-polyethersulfone (NH2-PES). Sulfonated polyether sulfone (S-PES) and NH2-PES have similar chemical structures that allow compatibility. Surpris- ingly enough, better results were obtained using amino-polyethersulfone. The best results have been obtained using SO2Cl-PES with 1.3 SO2Cl group per monomer unit crosslinked by 0.2 equivalent of NH2-PES. The membranes, less brittle than pristine SPES and insoluble in solvents such as DMAc, were characterized by TGA, DMA, DSC, ionic conductivity, transport numbers, and water swelling. The results showed that these membranes presented very promising performances for use in Proton Exchange Membrane Fuel Cells. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/7995 2013-01-01T00:00:00Z MABROUK, Walid OGIER, Lionel VIDAL, Serge SOLLOGOUB, Cyrille MATOUSSI, F. FAUVARQUE, J.F Synthesis and characterization of new ion exchange membranes made from chlorosulfonated polyethersul- fone (SO2Cl-PES) crosslinked by polyaminated crosslinking reagents have been performed. Two examples are described: one crosslinked by hexane diamine, the other by amino-polyethersulfone (NH2-PES). Sulfonated polyether sulfone (S-PES) and NH2-PES have similar chemical structures that allow compatibility. Surpris- ingly enough, better results were obtained using amino-polyethersulfone. The best results have been obtained using SO2Cl-PES with 1.3 SO2Cl group per monomer unit crosslinked by 0.2 equivalent of NH2-PES. The membranes, less brittle than pristine SPES and insoluble in solvents such as DMAc, were characterized by TGA, DMA, DSC, ionic conductivity, transport numbers, and water swelling. The results showed that these membranes presented very promising performances for use in Proton Exchange Membrane Fuel Cells. http://hdl.handle.net/10985/12454 Existence of a Critical Layer Thickness in PS/PMMA Nanolayered Films BIRONEAU, Adrien; SALEZ, Thomas; MIQUELARD-GARNIER, Guillaume; SOLLOGOUB, Cyrille An experimental study was carried out to investigate the existence of a critical layer thickness in nanolayer coextrusion, under which no continuous layer is observed. Polymer films containing thousands of layers of alternating polymers with individual layer thicknesses below 100 nm have been prepared by coextrusion through a series of layer multiplying elements. Different films composed of alternating layers of poly(methyl methacrylate) (PMMA) and polystyrene (PS) were fabricated with the aim to reach individual layer thicknesses as small as possible, varying the number of layers, the mass composition of both components, and the final total thickness of the film. Films were characterized by atomic force microscopy (AFM), and a statistical analysis was used to determine the distribution in layer thicknesses and the continuity of layers. For the PS/PMMA nanolayered systems, results point out the existence of a critical layer thickness around 10 nm, below which the layers break up. This critical layer thickness is reached regardless of the processing route, suggesting it might be dependent only on material characteristics but not on process parameters. We propose this breakup phenomenon is due to small interfacial perturbations that are amplified by (van der Waals) disjoining forces Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10985/12454 2017-01-01T00:00:00Z BIRONEAU, Adrien SALEZ, Thomas MIQUELARD-GARNIER, Guillaume SOLLOGOUB, Cyrille An experimental study was carried out to investigate the existence of a critical layer thickness in nanolayer coextrusion, under which no continuous layer is observed. Polymer films containing thousands of layers of alternating polymers with individual layer thicknesses below 100 nm have been prepared by coextrusion through a series of layer multiplying elements. Different films composed of alternating layers of poly(methyl methacrylate) (PMMA) and polystyrene (PS) were fabricated with the aim to reach individual layer thicknesses as small as possible, varying the number of layers, the mass composition of both components, and the final total thickness of the film. Films were characterized by atomic force microscopy (AFM), and a statistical analysis was used to determine the distribution in layer thicknesses and the continuity of layers. For the PS/PMMA nanolayered systems, results point out the existence of a critical layer thickness around 10 nm, below which the layers break up. This critical layer thickness is reached regardless of the processing route, suggesting it might be dependent only on material characteristics but not on process parameters. We propose this breakup phenomenon is due to small interfacial perturbations that are amplified by (van der Waals) disjoining forces http://hdl.handle.net/10985/11596 Confinement effect in PC/MXD6 multilayer films: Impact of the microlayered structure on water and gas barrier properties MESSIN, Tiphaine; FOLLAIN, Nadège; GUINAULT, Alain; MIQUELARD-GARNIER, Guillaume; SOLLOGOUB, Cyrille; DELPOUVE, Nicolas; GAUCHER, Valérie; MARAIS, Stéphane The transport properties were specifically investigated from water and gas permeation kinetics, and the corresponding permeation parameters were determined. The confinement effect of MXD6 in the multilayer structure was highlighted by comparing the permeability predicted from the series model equation with the experimental data. Although the MXD6 layers were not homogeneous and continuous for all membranes, water and gas permeabilities of the PC/MXD6 multilayer film were largely reduced. Such improvement of barrier properties was related to the change of the MXD6 structure, considering that the confinement of the MXD6 layers induced by PC layers allowed to bring chain orientation and to reduce the chain segment mobility in the MXD6 amorphous constrained zones. In addition, in the case of a PC/MXD6 multilayer structure well defined with continuous layers and relatively homogeneous thicknesses, the degree of crystallinity was slightly increased. Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10985/11596 2017-01-01T00:00:00Z MESSIN, Tiphaine FOLLAIN, Nadège GUINAULT, Alain MIQUELARD-GARNIER, Guillaume SOLLOGOUB, Cyrille DELPOUVE, Nicolas GAUCHER, Valérie MARAIS, Stéphane The transport properties were specifically investigated from water and gas permeation kinetics, and the corresponding permeation parameters were determined. The confinement effect of MXD6 in the multilayer structure was highlighted by comparing the permeability predicted from the series model equation with the experimental data. Although the MXD6 layers were not homogeneous and continuous for all membranes, water and gas permeabilities of the PC/MXD6 multilayer film were largely reduced. Such improvement of barrier properties was related to the change of the MXD6 structure, considering that the confinement of the MXD6 layers induced by PC layers allowed to bring chain orientation and to reduce the chain segment mobility in the MXD6 amorphous constrained zones. In addition, in the case of a PC/MXD6 multilayer structure well defined with continuous layers and relatively homogeneous thicknesses, the degree of crystallinity was slightly increased. http://hdl.handle.net/10985/12375 Structure and Barrier Properties of Multinanolayered Biodegradable PLA/PBSA Films: Confinement Effect via Forced Assembly Coextrusion FOLLAIN, Nadège; GUINAULT, Alain; SOLLOGOUB, Cyrille; GAUCHER, Valérie; DELPOUVE, Nicolas; MARAIS, Stéphane; MESSIN, Tiphaine Multilayer coextrusion processing was applied to produce 2049-layer film of poly(butylene succinate-co-butylene adipate) (PBSA) confined against poly(lactic acid) (PLA) using forced assembly, where the PBSA layer thickness was about 60 nm. This unique technology allowed to process semicrystalline PBSA as confined polymer and amorphous PLA as confining polymer in a continuous manner. The continuity of PBSA layers within the 80/20 wt % PLA/PBSA layered films was clearly evidenced by atomic force microscopy (AFM). Similar thermal events to the reference films were revealed by thermal studies; indicating no diffusion of polymers during the melt-processing. Mechanical properties were measured for the multilayer film and the obtained results were those expected considering the fraction of each polymer, revealing the absence of delamination in the PLA/PBSA multinanolayer film. The confinement effect induced by PLA led to a slight orientation of the crystals, an increase of the rigid amorphous fraction (RAF) in PBSA with a densification of this fraction without changing film crystallinity. These structural changes allowed to strongly improve the water vapor and gas barrier properties of the PBSA layer into the multilayer film up to two decades in the case of CO2 gas. By confining the PBSA structure in very thin and continuous layers, it was then possible to improve the barrier performances of a biodegradable system and the resulting barrier properties were successfully correlated to the effect of confinement on the microstructure and the chain segment mobility of the amorphous phase. Such investigation on these multinanolayers of PLA/PBSA with the aim of evidencing relationships between microstructure implying RAF and barrier performances has never been performed yet. Besides, gas and water permeation results have shown that the barrier improvement obtained from the multilayer was mainly due to the reduction of solubility linked to the reduction of the free volume while the tortuosity effect, as usually expected, was not really observed. This work brings new insights in the field of physicochemical behaviors of new multilayer films made of biodegradable polyesters but also in interfacial processes due to the confinement effect induced in these multinanolayer structures obtained by the forced assembly coextrusion. This original coextrusion process was a very advantageous technique to produce eco-friendly materials with functional properties without the help of tie layer, additives, solvents, surface treatments, or inorganic fillers. Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10985/12375 2017-01-01T00:00:00Z FOLLAIN, Nadège GUINAULT, Alain SOLLOGOUB, Cyrille GAUCHER, Valérie DELPOUVE, Nicolas MARAIS, Stéphane MESSIN, Tiphaine Multilayer coextrusion processing was applied to produce 2049-layer film of poly(butylene succinate-co-butylene adipate) (PBSA) confined against poly(lactic acid) (PLA) using forced assembly, where the PBSA layer thickness was about 60 nm. This unique technology allowed to process semicrystalline PBSA as confined polymer and amorphous PLA as confining polymer in a continuous manner. The continuity of PBSA layers within the 80/20 wt % PLA/PBSA layered films was clearly evidenced by atomic force microscopy (AFM). Similar thermal events to the reference films were revealed by thermal studies; indicating no diffusion of polymers during the melt-processing. Mechanical properties were measured for the multilayer film and the obtained results were those expected considering the fraction of each polymer, revealing the absence of delamination in the PLA/PBSA multinanolayer film. The confinement effect induced by PLA led to a slight orientation of the crystals, an increase of the rigid amorphous fraction (RAF) in PBSA with a densification of this fraction without changing film crystallinity. These structural changes allowed to strongly improve the water vapor and gas barrier properties of the PBSA layer into the multilayer film up to two decades in the case of CO2 gas. By confining the PBSA structure in very thin and continuous layers, it was then possible to improve the barrier performances of a biodegradable system and the resulting barrier properties were successfully correlated to the effect of confinement on the microstructure and the chain segment mobility of the amorphous phase. Such investigation on these multinanolayers of PLA/PBSA with the aim of evidencing relationships between microstructure implying RAF and barrier performances has never been performed yet. Besides, gas and water permeation results have shown that the barrier improvement obtained from the multilayer was mainly due to the reduction of solubility linked to the reduction of the free volume while the tortuosity effect, as usually expected, was not really observed. This work brings new insights in the field of physicochemical behaviors of new multilayer films made of biodegradable polyesters but also in interfacial processes due to the confinement effect induced in these multinanolayer structures obtained by the forced assembly coextrusion. This original coextrusion process was a very advantageous technique to produce eco-friendly materials with functional properties without the help of tie layer, additives, solvents, surface treatments, or inorganic fillers. http://hdl.handle.net/10985/13811 Breakup behavior of nanolayers in polymeric multilayer systems — Creation of nanosheets and nanodroplets FENG, Jingxing; BAER, Eric; OLAH, Andrew; SOLLOGOUB, Cyrille; MIQUELARD-GARNIER, Guillaume; GUINAULT, Alain; BIRONEAU, Adrien; ZHANG, Ziyou Multilayer films comprising polystyrene (PS)/polymethyl methalcrylate (PMMA) and PS/polycaprolatone (PCL) alternating nanolayers with varied layer thickness were fabricated by multilayer coextrusion. The nanolayers breakup phenomena of PMMA and PCL were characterized using atomic force microscopy (AFM), oxygen permeability, light transmission, wide-angle X-ray scattering (WAXS), and differential scanning calorimetry (DSC). The continuous layers started to break up into nanosheets and nanodroplets during the coextrusion process when the nominal layer thickness decreased to between 30 nm and 40 nm. Further decrease of the nominal layer thickness of PMMA and PCL resulted in less nanosheets and more nanodroplets. Oxygen permeability was effective for characterizing the onset thickness of layer breakup. The oxygen permeability for the PS/PCL system was modeled and demonstrated good correlation with estimated composition of continuous layers, nanosheets, and nanodroplets. Mon, 01 Jan 2018 00:00:00 GMT http://hdl.handle.net/10985/13811 2018-01-01T00:00:00Z FENG, Jingxing BAER, Eric OLAH, Andrew SOLLOGOUB, Cyrille MIQUELARD-GARNIER, Guillaume GUINAULT, Alain BIRONEAU, Adrien ZHANG, Ziyou Multilayer films comprising polystyrene (PS)/polymethyl methalcrylate (PMMA) and PS/polycaprolatone (PCL) alternating nanolayers with varied layer thickness were fabricated by multilayer coextrusion. The nanolayers breakup phenomena of PMMA and PCL were characterized using atomic force microscopy (AFM), oxygen permeability, light transmission, wide-angle X-ray scattering (WAXS), and differential scanning calorimetry (DSC). The continuous layers started to break up into nanosheets and nanodroplets during the coextrusion process when the nominal layer thickness decreased to between 30 nm and 40 nm. Further decrease of the nominal layer thickness of PMMA and PCL resulted in less nanosheets and more nanodroplets. Oxygen permeability was effective for characterizing the onset thickness of layer breakup. The oxygen permeability for the PS/PCL system was modeled and demonstrated good correlation with estimated composition of continuous layers, nanosheets, and nanodroplets. http://hdl.handle.net/10985/17916 Preparation of new proton exchange membranes using sulfonated poly(ether sulfone) modified by octylamine (SPESOS) MABROUK, Walid; OGIER, Lionel; SOLLOGOUB, Cyrille; VIDAL, Serge; DACHRAOUI, M.; FAUVARQUE, J.F Sulfonated poly(arylene ether sulfone) (SPES) has received considerable attention in membrane preparation for proton exchange membrane fuel cell (PEMFC). But such membranes are brittle and difficult to handle in operation. We investigated new membranes using SPES grafted with various degrees of octylamine. Five new materials made from sulfonated polyethersulfone sulfonamide (SPESOS) were synthetized with different grades of grafting. They were made from SPES, with initially an ionic exchange capacity (IEC) of 2.4 meq g−1 (1.3 H+ per monomer unit). Pristine SPES with that IEC is water swelling and becomes soluble at 80 °C, its proton conductivity is in the range of 0.1 S cm−1 at room temperature in aqueous H2SO4 1 M, similar to that of Nafion®. After grafting with various amounts of octylamine, the material is water insoluble; membranes are less brittle and show sufficient ionic conductivity. Proton transport numbers were measured close to 1. Sat, 01 Jan 2011 00:00:00 GMT http://hdl.handle.net/10985/17916 2011-01-01T00:00:00Z MABROUK, Walid OGIER, Lionel SOLLOGOUB, Cyrille VIDAL, Serge DACHRAOUI, M. FAUVARQUE, J.F Sulfonated poly(arylene ether sulfone) (SPES) has received considerable attention in membrane preparation for proton exchange membrane fuel cell (PEMFC). But such membranes are brittle and difficult to handle in operation. We investigated new membranes using SPES grafted with various degrees of octylamine. Five new materials made from sulfonated polyethersulfone sulfonamide (SPESOS) were synthetized with different grades of grafting. They were made from SPES, with initially an ionic exchange capacity (IEC) of 2.4 meq g−1 (1.3 H+ per monomer unit). Pristine SPES with that IEC is water swelling and becomes soluble at 80 °C, its proton conductivity is in the range of 0.1 S cm−1 at room temperature in aqueous H2SO4 1 M, similar to that of Nafion®. After grafting with various amounts of octylamine, the material is water insoluble; membranes are less brittle and show sufficient ionic conductivity. Proton transport numbers were measured close to 1. http://hdl.handle.net/10985/17968 Influence of crystallinity on gas barrier and mechanical properties of pla food packaging films GUINAULT, Alain; SOLLOGOUB, Cyrille; DOMENEK, Sandra; GRANDMONTAGNE, Anne; DUCRUET, Violette J. Crystallinity is well-known to have major effects on the gas barrier properties. However, its effect on gas barrier properties is often dependant on the studied material and is difficult to anticipate because two aspects of crystallinity have to be considered: the crystallinity degree and the crystalline morphology. PLA is known to recrystallize when heated at a temperature higher than its Tg ("cold" recrystalllisation). Different recrystallized samples have been obtained by compression-molding the extruded films in different conditions of heating. The crystallinity degree and morphology have been investigated and related to the gas barrier properties of the films. Since crystallinity also affects mechanical properties, the yield strength and the elongation at break have been measured. Fri, 01 Jan 2010 00:00:00 GMT http://hdl.handle.net/10985/17968 2010-01-01T00:00:00Z GUINAULT, Alain SOLLOGOUB, Cyrille DOMENEK, Sandra GRANDMONTAGNE, Anne DUCRUET, Violette J. Crystallinity is well-known to have major effects on the gas barrier properties. However, its effect on gas barrier properties is often dependant on the studied material and is difficult to anticipate because two aspects of crystallinity have to be considered: the crystallinity degree and the crystalline morphology. PLA is known to recrystallize when heated at a temperature higher than its Tg ("cold" recrystalllisation). Different recrystallized samples have been obtained by compression-molding the extruded films in different conditions of heating. The crystallinity degree and morphology have been investigated and related to the gas barrier properties of the films. Since crystallinity also affects mechanical properties, the yield strength and the elongation at break have been measured. http://hdl.handle.net/10985/14643 Impact of water and thermal induced crystallizations in a PC/MXD6 multilayer film on barrier properties MESSIN, Tiphaine; MARAIS, Stéphane; FOLLAIN, Nadège; CHAPPEY, Corinne; GUINAULT, Alain; MIQUELARD-GARNIER, Guillaume; DELPOUVE, Nicolas; GAUCHER, Valérie; SOLLOGOUB, Cyrille 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. Tue, 01 Jan 2019 00:00:00 GMT http://hdl.handle.net/10985/14643 2019-01-01T00:00:00Z MESSIN, Tiphaine MARAIS, Stéphane FOLLAIN, Nadège CHAPPEY, Corinne GUINAULT, Alain MIQUELARD-GARNIER, Guillaume DELPOUVE, Nicolas GAUCHER, Valérie SOLLOGOUB, Cyrille 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. http://hdl.handle.net/10985/13875 Reduced physical aging rates of polylactide in polystyrene/polylactide multilayer films from fast scanning calorimetry MONNIER, Xavier; FERNANDES NASSAR, Samira; DOMENEK, Sandra; GUINAULT, Alain; SOLLOGOUB, Cyrille; DARGENT, Eric; DELPOUVE, Nicolas The physical aging behavior of amorphous polylactide constrained against polystyrene in layers of 300 nm, thanks to the layer–multiplying co–extrusion process, was investigated by fast–scanning calorimetry (FSC). By cooling down the sample from the liquid state to the glassy one at very fast scanning rates, it was possible to investigate the structural relaxation of the polymer glass at high temperatures for which the time needed to reach the equilibrium was shortened. Therefore it was possible to perform the study of physical aging in experimental conditions providing an expanded view of the structural relaxation for short aging times. Taking benefit of this property, it was highlighted that the aging kinetics of polylactide occurred significantly slower in the multilayer film, in comparison with a bulk amorphous film. The process of recovery in the multilayer system was found to occur at similar rates, or even slower, than in a three–layer film in which polylactide reached its maximum extent of crystallinity. This was attributed to mobility hindrance that might be inherent to the extrusion conditions or associated with the presence of capped interfaces with polystyrene. Mon, 01 Jan 2018 00:00:00 GMT http://hdl.handle.net/10985/13875 2018-01-01T00:00:00Z MONNIER, Xavier FERNANDES NASSAR, Samira DOMENEK, Sandra GUINAULT, Alain SOLLOGOUB, Cyrille DARGENT, Eric DELPOUVE, Nicolas The physical aging behavior of amorphous polylactide constrained against polystyrene in layers of 300 nm, thanks to the layer–multiplying co–extrusion process, was investigated by fast–scanning calorimetry (FSC). By cooling down the sample from the liquid state to the glassy one at very fast scanning rates, it was possible to investigate the structural relaxation of the polymer glass at high temperatures for which the time needed to reach the equilibrium was shortened. Therefore it was possible to perform the study of physical aging in experimental conditions providing an expanded view of the structural relaxation for short aging times. Taking benefit of this property, it was highlighted that the aging kinetics of polylactide occurred significantly slower in the multilayer film, in comparison with a bulk amorphous film. The process of recovery in the multilayer system was found to occur at similar rates, or even slower, than in a three–layer film in which polylactide reached its maximum extent of crystallinity. This was attributed to mobility hindrance that might be inherent to the extrusion conditions or associated with the presence of capped interfaces with polystyrene.