Proper preparation and analysis of polymer-clay nanocomposites

2 Proper preparation and analysis of polymer-clay nanocomposites 

An excellent example of the proper protocol to employ in regard to the assessment of the mechanical properties of polymer-clay nanocomposites is provided by the work of Fornes and Paul [5]. The Young s modulus of polymer composites formed by symmetrical, large, reinforcing dispersed phases in polymers where the adhesion of the polymer to the dispersed phases is large can be approximated by  

Clay is very anisotropic and small with a large surface area and modulus. To account for these characteristics of clay in a polymer, Fornes and Paul evaluated two analytical methods, those of Halpin-Tsai [6,7,8] and Mori-Tanaka [9], that were developed to calculate the Young s moduli for the types of morphology that can be associated with clay particles. Assuming that the polymer and the reinforcing dispersed phase are the only components in the polymer composite, the volume 

Substituting Equation 5.4 into Equation 5.3, Young s modulus can be expressed as  

The expression for the Halpin-Tsai equation that is applicable to polymer-clay nanocomposites that have the clay particles oriented in the direction of the applied stress includes the aspect ratio (A) of the particle in the equation. 

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