| Abstract
| - The present paper describes the synthesis and characterization of nanocomposite materialsbuilt from the assembly of organic polymers and two-dimensional host materials, particularlyreviewing those composed of layered double hydroxide (LDH) inorganic frameworks. Whenthe meaning commonly adopted for nanocomposites is narrowed, the system is constitutedof sheets lying on top of each other in which covalent forces maintain the chemical integrityand define an interlamellar gap filled up with the polymer guest. The situation is differentfrom an inorganic filler dispersed into a polymeric matrix. The incorporation of polymerbetween the galleries proceeds via different pathways such as coprecipitation, exchange, insitu polymerization, surfactant-mediated incorporation, hydrothermal treatment, reconstruction, or restacking. The latter method, recently effective via the exfoliation of the LDH layers,appears to be more favorable, in terms of crystallinity, to capture monomer entities thanthe whole polymer. The nanocomposites are enlisted according to the preparation pathways.It is found that these multicomponent systems are thermally more stable than the pristineinorganic compounds, leading, for example, to potential applications in flame-retardantcomposites. A large variety of LDH/polymer systems may be tailored considering the highlytunable intralayer composition coupled to the choice of the organic moiety. The paperconcludes with a brief discussion underlining the perspectives. Despite their appeal, thepolymer/LDH class of nanocomposites has not yet been extensively studied for applications.
- This paper covers an overview on different aspects of organic polymer incorporation between the sheets of a 2D inorganic framework and particularly emphasizing the recent developments in the synthesis and characterization of nanocomposites based on layered double hydroxide host materials. After a general background to polymer intercalation is provided, the different pathways are illustrated: in situ polymerization, restacking and reconstruction processes, and direct exchange. A state of the art is presented, and a few hints of their potential applications in comparison to existing systems are also provided.
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