title: Structural and microstructural studies of montmorillonite-based multilayer nanocomposites.
abstract: OBJECTIVE
  Montmorillonite, an abundant raw material, is a good candidate to obtain textured nanocomposites. However, the resulting structure of the composite depends on the dispersant used. This work aims at investigating the effect of organic polysaccharides, namely carboxymethylcellulose (CMC) or chitosan (Ch) differing by their side groups, on the resulting structure of montmorillonite-based nanocomposites.
  
  
  METHODS
  The effect of sodium hexametaphosphate and of two polysaccharide derivatives (carboxymethylcellulose and chitosan) combined with montmorillonite on the structure and microstructure of resulting composite films was investigated using particle size analysis, rheological measurements, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy and flexural properties measurements of the textured films.
  
  
  RESULTS
  Results showed that the film structure and microstructure depend on the additive. The high organization (and resulting toughness) of the montmorillonite/sodium hexametaphosphate films results from an exfoliated then layered microstructure, whereas the addition of polysaccharide derivatives leads to the particle agglomeration. In this case, two mechanisms are in competition: surface adsorption and intercalation between exfoliated platelets.
authors.affiliation: Groupe d'Etude des Matériaux Hétérogènes, ENSCI, 12 rue Atlantis, 87068 Limoges, France.
authors.forename: David
authors.initials: D
authors.lastname: Kpogbémabou
authors.affiliation: Groupe d'Etude des Matériaux Hétérogènes, ENSCI, 12 rue Atlantis, 87068 Limoges, France.
authors.forename: Fayza
authors.initials: F
authors.lastname: Gridi-Bennadji
authors.affiliation: Lafarge Centre de Recherche, 95 rue du Montmurier, BP15 38291 Saint Quentin Fallavier Cedex, France.
authors.forename: Lê Chiên
authors.initials: LC
authors.lastname: Hoang
authors.affiliation: Lafarge Centre de Recherche, 95 rue du Montmurier, BP15 38291 Saint Quentin Fallavier Cedex, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Ghilardi
authors.affiliation: Lafarge Centre de Recherche, 95 rue du Montmurier, BP15 38291 Saint Quentin Fallavier Cedex, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Jacquet
authors.affiliation: Groupe d'Etude des Matériaux Hétérogènes, ENSCI, 12 rue Atlantis, 87068 Limoges, France.
authors.forename: Agnès
authors.initials: A
authors.lastname: Smith
authors.affiliation: Groupe d'Etude des Matériaux Hétérogènes, ENSCI, 12 rue Atlantis, 87068 Limoges, France. Electronic address: claire.peyratout@unilim.fr.
authors.forename: Claire
authors.initials: C
authors.lastname: Peyratout
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000737:chemistry*; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D006244:Hardness; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008968:Molecular Conformation; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D010710:Phosphates / Q000737:chemistry*; D012212:Rheology; D013818:Thermogravimetry
chemical_list: D010710:Phosphates; D001546:Bentonite; D048271:Chitosan; D002266:Carboxymethylcellulose Sodium; C009285:sodium polymetaphosphate
keywords: Clay; Exfoliation; Intercalation; Interface; Natural polymers; Surface