Strategies for improving the performance of polymeric matrix/clay nanocomposites

LEANDRO LUDUEÑA; VERA ALVAREZ

Advances in Materials Science Research

Nova Publishers

Año: 2011;

This review is designed to be a comprehensive source for polymer/clay nanocomposite research. This work focuses on several strategies to obtain well-dispersed and, so that with improved mechanical properties, nanocomposites. The strategies are based on the chemical modification of the clay and on the variation of processing conditions. The different reviewed works used wide angle X-ray diffractometry (XRD), transmission electron microscopy (TEM) and melt rheology in order to analyze the clay dispersion degree inside the matrix. The effect of changing processing parameters (temperature, speed of rotation of the screws and residence time) on the morphology and mechanical properties of polymer/clay nanocomposites was also analyzed. Different processing techniques, such us stretching and injection molding, compression molding, were also reviewed and the effect of each one on the final properties of nanocomposites were determined. It was shown that the variation of extrusion parameters not always has significant influence on the final properties of the nanocomposite, which is mainly related with the fact that, when shear forces are used for polymer/clay melt blending, the critical step for obtaining a high degree of dispersion of reinforcement within the matrix is the optimization of a balance between the polymer/clay chemical compatibility and the thermo-mechanical stability of the clay organo-modifier. Finally, it was shown that using certain processing techniques in which different fluid regions are subjected to extensional flow, the clay particles can be oriented preferentially in that direction improving the mechanical properties of the nanocomposite.