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Last name: PEUVREL-DISDIER
First name: Edith
International audience
International audience
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Graphene nanoplatelets (GNP) of various sizes were mixed with polypropylene (PP) in an internal mixer to prepare composites. The effects of mixing conditions, GNP size and concentration in composites were investigated. The composites were characterized at different scales, using electron microscopy, X-ray diffraction, thermogravimetric...
This paper is devoted the behavior of suspension of fiber-spheres particles. We pointed out by experimental and numerical observations that the Jeferry approximation is no more valid as the sphere particle concentration increases.
Dans un fluide Newtonien, l'orientation d'une fibre est parfaitement décrire par l'équation de Jeffery. Dans cette étude,on utilise un rhéomètre numérique pour étudier l'évolution d'une fibre dans un champ de cisaillement simple pour des fluidesviscoélastiques Oldroyd-B. Pour les fluides viscoélastiques, la période de rotation augmente avec le...
Une méthode numérique a été développé afin de permettre le calcul du mouvement de particules solides dans un fluide en cisaillement. Les calculs sur un volume élémentaire permettent d'étudier l'évolution de l'orientation de particules allongées pour un fluide chargés en particules sphériques. Finalement, des observations expérimentales sont...
International audience
The objective of this work was to develop a microscale model allowing to describe the growth of gas bubbles during the foaming of a rubber matrix in injection moulding conditions. The description of the foaming at the level of the bubble is based on a model first proposed by Amon and Denson [1]. The model describes the growth of numerous cells...
Polypropylene (PP)-based nanocomposites reinforced with three different organoclays (Dellite© 67 G, Cloisite© 20, and Cloisite© 30B) were prepared via melt-mixing in an internal mixer. The three organoclays differ essentially via their organic modifier and interlamellar distance. The nanocomposites microstructure was characterized at different...
International audience
The objective of this work is to develop a numerical model allowing to predict the foaming process of a rubber matrix in injection molding conditions. This is achieved in two parts. The first one is a microscale model that describes the growth of a bubble, based on Amon and Denson's work [1], according to whom the foam is divided into identical...
International audience
The objective of this work is to model the chemical foaming of an industrial EPDM rubber compound formulation. The chemical foaming is caused by OBSH chemical decomposition with nitrogen formation. The vulcanisation system is sulphur based. Both reactions are controlled by the thermal history.Two approaches have been compared to model the...
The objective of this work is to model the chemical foaming of an industrial rubber compound formulation in controlled thermal history. The chemical foaming is caused by a chemical agent (CA) decomposition with nitrogen formation. The vulcanisation system is sulphur based. Both reactions are controlled by the thermal history.The objective is to...
In this work, modelling of physical foaming extrusion of LDPE is carried out in order to achieve a better understanding of the mechanisms involved in foam manufacturing. Foaming by extrusion is a four-step process. First, the pellets are introduced and molten in an extruder. Gas is then injected under pressure and dissolved in the polymer...
Unusual self-organization of sepiolite fibbers have been found during the synthesis of sustainable nanocomposites. These auto-structured networks are synthesized starting with an epoxidized linseed oil (ELO), a bio-based hardener of dicarboxylic class and sepiolite fibbers. For the first time, the auto-organization of sepiolite fibbers into...
Le renforcement des polymères est très souvent réalisé par des nanocharges en raison de leursgrandes surfaces de contact, jouant un rôle particulier sur leurs comportements. Parfois de formesanalogues à celles de fibres, ces charges jouent un rôle important dans les propriétés thermiques,mécaniques, optiques ou barrières et permettent de...
This paper aims at a better understanding of the polypropylene (PP) physical extrusion foaming process with the objective of obtaining the lowest possible foam density. Two branched PPs were compared to the corresponding linear ones. Their shear and elongation viscosities were measured as well as their crystalline properties. Trials were...
In the present work, a prototype was developed to observe the flow behavior of viscous fluids (10^3 to 10^5 Pa.s) under free surface shear. The geometry of the prototype is an eccentric Couette cell where both cylinders can rotate in the same or opposite directions. Transparent windows permit in-situ observations during flow. The design,...
This study aims at a better understanding of the polypropylene (PP) foamability by physical extrusion foaming. Trials were conducted in a single screw extruder equipped with a gear pump for the gas dissolution step (same extrusion parameters, 1wt% CO2) and a static mixer cooler allowing to decrease the melt temperature before the final die...
This study aims to better understand the polypropylene (PP) foamability by physical extrusion foaming comparing branched chains with strain hardening versus linear ones. Trials were conducted in a single screw extrusion equipped with a gear pump for the gas dissolution step (same extrusion parameters, 1wt% CO2) and a static mixer cooler...
International audience
This study aims to better understand the polypropylene (PP) foamability by physical extrusion foaming comparing branched chains with strain hardening versus linear ones. Trials were conducted in a single screw extrusion equipped with a gear pump for the gas dissolution step (same extrusion parameters, 1wt% CO2) and a static mixer cooler...
Abstract In the present work, a prototype was developed to observe the flow behavior of viscous fluids under free surface shear and determine an adhesion energy in this flow geometry. The geometry consists of an eccentric Couette cell (outer cylinder radius of 89.5 mm, inner cylinder radius of 43.75 mm and minimal gap of 3 mm) that can be used...