REMEDIOS MESA DE LEÓN [Material gráfico]

ÁLBUM FAMILIAR CASA DE COLÓNCopia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201

PLA-based ternary systems combining plasticizer and nanofillers: Influence of native clay on aging

International audienc

Structural evolution of poly(lactic acid)/poly(ethylene oxide)/unmodified clay upon ambient ageing

International audienc

PLA-based ternary systems combining plasticizer and nanofillers: Influence of native clay on aging

International audienc

Effet de la montmorillonite sur la morphologie et les propriétés mécaniques des mélanges poly(éthylène-terephtalate) / polyéthylène : rôle du surfactant

Journée Industrielle de l'Institut Carnot MINES NANOMATERIAUX Mines Paris JANVIER 2011Des mélanges immiscibles de Poly-(Ethylène Téréphtalate) PET et Poly-(Ethylène) basse densité LDPE ont été compatibilisé par ajout de Montmorillonite organiquement modifiée par différents types de surfactant. La caractérisation de la morphologie des nanocomposites obtenus par Microscopie Electronique à Balayage et Diffraction des Rayons X montrent une bonne dispersion des nanocharges accompagnée par un affinement de la morphologie des mélanges. En se basant sur les analyses thermogravimétriques (ATG) et les résultats des tests mécaniques (traction et choc), il apparait que les propriétés mécaniques des mélanges PET/PE/nanocharges dépendent à la fois de la nature chimique et de la stabilité thermique du surfactant utilisé pour la modification organique des nanoparticules lamellaires

Poly(ethylene oxide)/Poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonate) (PEDOT:PSS) Blends: An Efficient Route to Highly Conductive Thermoplastic Materials for Melt-State Extrusion Processing ?

International audienceBlends of poly(ethylene oxide) (PEO) with poly- (3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PE- DOT:PSS) were investigated for the preparation of electrically conductive films using melt-state extrusion processing techniques. High molecular weight PEO is selected as a melting carrier to enable the extrusion processing of PEDOT:PSS. A drop-casting technique from aqueous solutions is first investigated to produce model PEO/PEDOT:PSS blends and identify the influence of relevant parameters on the final electronic conductivity. A low percolation threshold (approximately 9 wt % PEDOT:PSS into PEO) and high electronic conductivities (10−1000 S/cm) are detected. These performances are correlated to homogeneous blend morphologies and miscibility effects arising from strong PEO/PSS interactions detected by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX), atomic force microscopy (AFM), and differential scanning calorimetry (DSC). Storage time and water ionic content have negative impacts on the electronic conductivity. The procedure was then adapted to prepare PEO-rich blends using twin-screw extrusion at 120 °C. A strong negative impact of the thermomechanical treatment was attested for PEO/PEDOT:PSS blends due to phase segregation phenomena induced by extrusion. However, an acidic post-treatment on extruded and molded thin films efficiently restored high electronic conductivities up to 4 S/cm for PEO-rich blends with 40 wt % PEDOT:PSS due to the removal of insulating phases. Such thermoplastic materials were found to be competitive with traditional thermoplastic solutions and thus represent efficient candidates for the development of thermoplastic electrodes using conventional and advanced processing technologies of the plastic industry

Compatibilization mechanism induced by organoclay in PMMA/PS blends

In this work, the effect of adding organoclay (Cloisite 20A) to a poly(methyl metacrylate) (PMMA)/polystyrene (PS) blend was evaluated in order to understand the compatibilization mechanism taking place. The blend morphology was quantified using micrographs obtained by scanning electron microscopy and observed by transmission electron microscopy. The state of dispersion of the clay was studied using small angle X-ray scattering and wide angle X-ray scattering and by applying the Carreau-Yasuda with a yield stress model to small amplitude oscillatory shear (SAOS) data. Morphological analyses revealed that the clay was intercalated, that its addition resulted in a decrease in the size of the dispersed phase and that it was preferentially located at the interface, except in the case of saturated interfaces, in which case the remaining clay was dispersed in PMMA. By applying the simplified Palierne model to SAOS experiments, the interfacial tension between the polymers forming the blend was inferred and shown to decrease upon addition of clay. The relaxation spectra inferred from the SAOS data, using the Honerkamp and Weese method, revealed four relaxation times: Relaxation of PMMA and PS chains, relaxation of the droplet shape, as well as an additional relaxation phenomenon attributed to the Marangoni stress. Although Marangoni stresses have already been studied in the case of blends compatibilized by block copolymers, this is the first time that it has been evidenced in the case of a clay as compatibilizer. (C) 2017 The Society of Rheology.Natural Sciences and Engineering Research Council of Canada (NSERC)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Ecole de technologie superieure (ETS)Mines Douai, Dept Polymer & Composites Technol & Mech Engn, Douai, FranceEcole Technol Super, Dept Mech Engn, Montreal, PQ H3C 1K3, CanadaUniv Sao Paulo, Met & Mat Engn Dept, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Sea Sci, Santos, BrazilUniv Sao Paulo, Met & Mat Engn Dept, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Sea Sci, Santos, BrazilNSERCFAPESPCNPqCAPESETSWeb of Scienc

Injection de nanocomposites PP/argile à base de mélanges maîtres concentrés: Relation entre dispersion de la nanocharge et paramètres de moulage

National audienc

Multi-walled carbon nanotube filled polypropylene nanocomposites based on a masterbatch route: Optimization of CNTs dispersion

International audienc

In-situ fibrillation of polypropylene/polyamide 6 blends: Effect of organoclay addition

International audienc