For nanocomposite synthesis, polymer chains must diffuse into the galleries
between clay layers to produce structures ranging from intercalated to exfoliated.
Intercalation occurs when a small amount of polymer penetrates into the galleries,
resulting in finite expansion of the clay layers. This leads to a well-ordered multilayered
structure with a repeat distance of a few nanometers, and is observed in systems with
limited miscibility. Extensive polymer penetration leads to exfoliation or delamination of
clay layers. An exfoliated nanocomposite consists of nanometer thick platelets distributed
homogeneously throughout the polymer matrix. In contrast, when the polymer and
silicate are immiscible, the layers do not separate and exist as agglomerates or tactoids.
Intercalation and exfoliation are the desirable arrangement for improving the properties
of nanocomposites. Due to the hydrophilic surface properties of pristine LDH, LDHs
modified by organic molecules are normally required for miscibility with synthetic
polymers. These modified LDH-based nanocomposites have shown improved mechanical
properties, barrier properties, heat stability and flame retardancy (Nyambo and others
2008; Costa and others 2008; Bugatti and others 2010). Moreover, additional properties
can be brought to the nanocomposites due to the organic molecules (Costantino and
others 2009; Tammaro and others 2009; San Roman and others 2013).
Food spoilage due to undesirable microbial growth is a common factor which
shortens the shelf life of food products and can cause food borne illness outbreaks. The
addition of antimicrobial agents (active compounds that kill or prevent the growth of
microorganisms) to foods or food surfaces during processing is an effective technique
that is frequently employed to eliminate food borne pathogens. However, the
antimicrobial activity may be rapidly lost due to inactivation of the antimicrobials by