In recent years, a significant increase in interest of polymer nanocomposites, a relatively new group of materials is observed. Polymer nanocomposites have attracted great attention worldwide academically and industrially due to the exhibition of superior properties such as modulus, strength and toughness. However, polymer nanocomposites have added the advantage of lower density and ease of process ability. Polymer based nanocomposites are gaining an increasing interest of the substantial improvements in material properties such as gas and solvent barrier, toughness and mechanical strength etc. as compared to micro or macro scaled composites.<br /> Although polymers can be used as structural materials without reinforced, their usage gets limited due to insufficient mechanical properties. Relatively low strength coupled with low impact strength is a characterization of polymer materials. Owing to their nanometer sizes of the inorganic filler, nanocomposites exhibit markedly improved properties when compared to the pure polymers or their traditional composites. The physical properties exhibited by polymeric nanocomposites are determined by the quality and the nature of dispersion of the nano fillers in the polymer matrix. However, it is well known that the surface energy substantially increases with the decrease of particle size. Consequently, nanoparticles tend to aggregate in order to reduce the total surface energy, creating a pervasive manufacturing challenge. Polymer nanocomposites have revealed clearly the property advantages that nanomaterial additives can provide in comparison to both their conventional filler counterparts and base polymer. Properties which have been shown to undergo substantial improvement include:<br />• Mechanicals such as (strength, modulus and dimensional stability).<br />• Improved solvent and heat resistance and decreased flammability.<br />• Decreased permeability to gases, water and hydrocarbons.<br />• Thermal stability and heat distortion temperature.<br />• Chemical resistance.<br />• Flame retardancy and reduced smoke emissions.<br />• Surface appearance.<br />• Electrical conductivity.<br />• Optical clarity in comparison to conventionally filled polymers. <br /><br /> Assist. Lec. Leal Abdullah Hamza<br />