Rheology of nanocomposites

Cloisite 30B methyl, tallow, bis-2-hydroxyethyl, quaternary ammonium chloride, MT2EtOH 1.85 

Cloisite 6A dimethyl, dihydrogenated tallow, quaternary ammonium chloride, 2M2HT 3.51 

Cloisite lOA dimethyl, benzyl, hydrogenated tallow, qnatemary ammonium chloride, 2MBHT 1.92 

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Choi S, Lee KM, Han CD (2004) Effects of triblock copolymer architecture and the degree of functionalization on the oiganoclay dispersion and rheology of nanocomposites. Macromolecules 37 7649-7662... 

Hoffmann B, Kressler J, Stopelmann G, Friedrich C, Kim GM (2000) Rheology of nanocomposites based on layered silicates and polyamide-12. Colloid Polym Sd 278 629-639... 

Understanding the melt rheology of rubber nanocomposites is crucial from the processing perspective. Bandyopadhyay et al. [37] have studied the melt flow behavior of rubber-silica hybrid nanocomposites in a capillary rheometer. 

Krishnamoorti R, Giannelis EP (1997) Rheology of end-tethered polymer layered silicate nanocomposites. Macromolecules 30 4097-4102... 

Rheology of various polymer layered-silicate nanocomposites - intercalated, exfoliated and end-tethered exfoliated (prepared by in-situ polymerization from reactive groups tethered to the silicate surface), have been performed in a conventional melt-state rheometer in both oscillatory and steady shear modes. These experimental studies have provided insight into the relaxation of polymer chains when confined by the layers of inorganic silicates, as well as the role of shear in orienting the layered nanocomposites. 

Hadjistamov (1999) examined the effect of nanoscale silica on the rheology of silicone oil and uncured epoxy-resin (araldite) systems. Shear thickening and yield-stress-like behaviour were observed and found to be due to a build-up of network structure associated with the nanocomposite phase. 

CHI 05] Chiou B.S., Yee E., Glenn G.M., etal, Rheology of starch-clay nanocomposites ,... 

The results observed in this ehapter emphasize that the microcomposites rheology description models do not give adequate treatment of melt viscosity for particulate-filled nanocomposites. The correct description of the nanocomposites rheological properties can be obtained within the frameworks of viscous liquid flow fractal models. It is significant, that such an approach differs principally from the used ones to describe microcomposites. So, nanofiller particles aggregation reduces both melt viscosity and elastic modulus of nanocomposites in the solid-phase state. For microcomposites, melt viscosity enhancement is accompanied by elastic modulus increase. 

Hence, the results stated above confirmed that the models, developed for the microcomposites rheology description, did not give melt viscosity adequate treatment for nanocomposites polymer/oiganoclay as well. And as earlier, the indieated nanoeomposites iheologieal properties deseription ean be obtained within the fiamewoik of a viseous liquid flow fractal model. Na -montmorillonite plates aggregation in paekets (tactoids) simultaneously reduces both melt viscosity and elasticity modulus in solid-phase state of nanocomposites. 

Kozlov, G. V. Tlenkopachev, M. A. Zaikov, G. E. The rheology of particulate-filled polymer nanocomposites. In Polymer Yearbook-2011. Polymers, Composites and Nanocomposites. Ed. Zaikov, G. Sirghie, C. Kozlowski, R. New York, Nova Science Publishers, Inc. 2011,157-165. 

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