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MMT clay-based polymer nanocomposites have been widely studied because of their low cost and unique characteristics, as well as their applications in commercial sectors. The aim of this work was to evaluate the effect of MMT silylated by 3-aminopropyltriethoxysilane and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane on the mechanical behaviour of MMT/epoxy nanocomposites by evaluation of dynamical mechanical analysis and nanoindentation technique. The silicate clay layers were dispersed in the epoxy matrix by sonication process obtaining the intercalation of the epoxy resin inside the inorganic galleries of MMT. The results showed that the MMT modified with N-(2-aminoethyl)-3- aminopropyltrimethoxysilane, which is characterized by the longer alkyl functional group, exhibits an higher compatibility with polymer matrix and improved mechanical properties.

Summary: A polymer-clay nanocomposite based on Poly(butyleneterephthalate)(PBT) and an innovative organoclay has been synthesized via intercalation ofBis(hydroxyethyl terephthalate) (BHET) in Na-Montmorillonite layers. Chemical andphysical properties of this nanocomposite have been studied in comparison to otherPBT/nanocomposites based on two commercial organoclay: Cloisite 25A and SomasifMEE. Nanocomposites have beenprepared viamelt compounding using atwin-screwextruder, with extrusion rate of 150 rpm. Samples were characterized by usingwide-angle X-ray diffraction, TEM, thermal and mechanical analysis. Introduction In recent years polymer/layered silicate(PLS) nanocomposites have attractingincreasing interest in academia and indus-try because of their remarkable improve-mentsinmaterialpropertieswithrespecttopristine polymer or conventional micro andmacro-composites. They exhibit high mod-uli, [1–3] increased strength and heat resis-tance, [4] decreasedgaspermeability [5–7] andflammability.

This study describes the prepn. and the characterization of nanocomposites obtained by dispersion of amino-functionalised clays in DGEBA based adhesives. The amino-functionalised clays were obtained through silylation of Na+ Cloisite with three different aminosilanes such as A1100 (3-aminopropyltriethoxysilane), A1120 (N(beta-aminoethyl)y-aminopropyltrimethoxy-silane) and A1130 (Triaminofunctional silane). The presence of amino moieties on the layered silicates was confirmed by FTIR, thermal gravimetric and X-ray diffraction anal. In particular it was evidenced that the d-spacing between platelets constituting the tactoid filler increases as shorter is the org. chains of the different silanes. The nanocomposites obtained by dispersing the amino functionalised clays into a com. epoxy adhesive were characterised in terms of thermal and mech. behavior. (c) 2008 American Institute of Physics.