A comparative study of the synergistic effects between nanofillers and carbon black in the mechanical reinforcement of a hydrocarbon polymer matrix

In this work, hybrid systems based on a hydrocarbon polymer such as poly(1,4-cis-isoprene), a nanostructured filler such as CB and various types of nanofillers were investigated. Clays modified with an ammonium salt (organoclays, OC), carbon nanotubes (CNT) and nano-graphite (nG) were the nanofillers. The crystalline order in the nano-fillers, if present, was studied through X-ray diffraction. The structure of pristine nanofillers and polymer composites was investigated through transmission electron microscopy. Tensile measurements were performed on the composites assessing the initial modulus and the ultimate properties. Dynamic mechanical measurements in shear mode were carried out, determining storage G' and loss G'' moduli as a function of the strain amplitude, investigating the linearity of the dynamic behaviour at low strains. The mentioned investigations were performed on composites containing only the nanofiller as well as the hybrid filler systems. A comparison of the two sets of results is discussed, proposing possible ways to rationalize the the effect of the nano-filler within the materials. In particular, the synergies developed by the hybrid filler systems, if any, are highlighted.