ABSTRACT
In general, layered silicates have a layer thickness on the order of 1 nm and a very high aspect ratio (i.e., 10-1000). A small percent fraction of layered silicates that are properly dispersed throughout the polymer matrix thus creates a much higher surface area for polymer/filler interaction as compared to conventional composites. Depending on the nature of the components (layered silicate, organic cation, and polymer matrix) used and the method of preparation, three main types of composites may be obtained when layered clay is associated with a polymer (see Fig. 4.1) (Alexandre and Dubois, 2000; Sinha Ray and Okamoto, 2003): (a) Phase-separated structure: When the organic polymer is
interacted with inorganic clay (unmodified clay), the polymer is unable to intercalate within the clay layers and the clay is
dispersed as aggregates or regular stacks of layers formed by stacking together within the polymer matrix. The obtained composite structure is considered “phase separated.” The properties of phase-separated polymer-clay composites are in the range of traditional microcomposites (Olad, 2011).
