Phase morphology and rheological behavior of polymer/layered silicate nanocomposites

Rheological behavior of polymer/layered silicate nanocomposites an strongly dependent not only upon their microstructure but also upon the interfacial characteristics. Different phase morphology (intercalated or exfoliated) o f polymer/clay is obtained according to interfacial characteristics between polymer chains and clay. In intercalated structure, the presence of random ly oriented anisotropic stacks of silicate layers is responsible for the en hancement of both moduli. The PS/clay nanocomposites exhibit a slight enhan cement at low frequency because of its simple intercalated structure and li ttle interaction. On the other hand, the PS-co-ma/clay nanocomposites have a similar intercalated structure but exhibit a distinct plateau-like behavi or at low frequency since the PS-co-ma has a strong attractive interaction with the silicate layers. Finally, PE-g-ma/clay nanocomposites display an e xfoliated structure, which exhibit both a distinct plateau-like behavior at low frequency and enhanced moduli at high frequency. Percolation structure as well as large interfacial area between polymer chains and clay are resp onsible for the theological behavior.