| Titre : |
Enhanced dispersion and mechanical behavior of polypropylene composites compounded using extension-dominated extrusion |
| Type de document : |
texte imprimé |
| Année de publication : |
2020 |
| Article en page(s) : |
p. 281-301 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Catégories : |
Caractérisation
Charges (matériaux)
Cisaillement (mécanique)
Composites -- Propriétés mécaniques
Composites polymères
Dispersions et suspensions
Extrudeuse bi-vis
GraphèneLe graphène est un cristal bidimensionnel (monoplan) de carbone dont l'empilement constitue le graphite. Il a été isolé en 2004 par Andre Geim, du département de physique de l'université de Manchester, qui a reçu pour cette découverte le prix Nobel de physique en 2010 avec Konstantin Novoselov. Il peut être produit de deux manières : par extraction mécanique du graphite (graphène exfolié) dont la technique a été mise au point en 2004, ou par chauffage d'un cristal de carbure de silicium, qui permet la libération des atomes de silicium (graphène epitaxié). Record en conduction thermique jusqu'à 5300 W.m-1.K-1. C'est aussi un matériaux conducteur.
Matières plastiques -- Extrusion
Nanoparticules
Nanotubes
Noir de carbone
Polypropylène
Rhéologie
|
| Index. décimale : |
668.4 Plastiques, vinyles |
| Résumé : |
The process of dispersing filler in polymer matrix is vital to the behavior of polymer composites. The current study involves understanding the extent of dispersion of filler by only varying the nature of mixing during the process. Identical polymer composite materials are processed via two different kinds of mixing sections on the screw in a twin-screw extruder, differing in the type and amount of stress they impose on the filler agglomerate. An aggressive (900) Kneading Block (KB) mixing section is compared with recently developed Extensional Mixing Elements (EMEs), which impart extension dominated mixing while KB imparts shear dominated mixing. Various EME geometries of different levels of aggressiveness were computationally studied and validated. Composites obtained from KB are compared with composites processed using five different EME geometries. Three composites of Polypropylene (PP) filled with carbon black, graphene nano platelets and carbon nanotubes were studied independently. Composites processed through EMEs display about an order of magnitude better dispersion of filler agglomerate over the composites processed through KB. In addition, enhanced modulus and yield stress is observed for composites processed through EMEs. An improvement of 63% to 266% in the strain achieved for EME processed composites is seen under biaxial film stretching. |
| Note de contenu : |
- INTRODUCTION : Previous work - Extensional Mixing Element (EME) - Polymer systems of interest
- COMPUTATIONAL VALIDATION OF EMEs OF VARYING DEGREES OF AGGRESSIVENESS
- EXPERIMENTAL : Materials - Dispersion and liquid feeding - Extrusion - Injection molding - Shear rheometry - Scanning Electron Microscopy - Optical microscopy - Mechanical studies - Biaxial stretching - Differential Scanning Calorimetry
- RESULTS AND DISCUSSION : Processability - Shear behavior - Dispersion performance - Optical analysis - Mechanical behavior |
| DOI : |
https://doi.org/10.3139/217.3899 |
| En ligne : |
https://drive.google.com/file/d/1_aeFg7HIJbuJL8hMm38x_T9BSX1ys3OB/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34494 |
in INTERNATIONAL POLYMER PROCESSING > Vol. XXXV, N° 3 (07/2020) . - p. 281-301
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Enhanced dispersion and mechanical behavior of polypropylene composites compounded using extension-dominated extrusion in INTERNATIONAL POLYMER PROCESSING, Vol. XXXV, N° 3 (07/2020)
