Hybrid filler networks from nano-fillers

In this work, nanocomposites made of poly-1,4-cis-isoprene (IR) and nano-fillers such as either organoclays or multi wall CNT were considered. Composites were prepared by melt compounding, also in the presence of a major amount of carbon black. Morphologies were studied by means of X-ray Diffraction and Transmission Electron Microscopy and tensile static and dynamic-mechanical properties were determined on vulcanized samples. The formation of a filler network was investigated by evaluating the initial modulus from stress-elongation curves obtained in tensile tests, and analyzing the modulus data as a function of the nano-filler content by applying mechanical models proposed in the literature. Molecular modeling calculations showed a low energy interaction of fullerenes and IR polymer chains but also a preferential tendency to self aggregation of fullerenes, when a COOH group was introduced in the polymer chain. A discussion is proposed to comment vis a vis the presented results.