Conventional rubber nanocomposites

Nanocomposites with silica nanoparticles have been prepared in poly-dimethylsiloxanes, butadiene, styrene-butadiene, acrylonitrile-butadiene, acrylic and ethylene-propylene diene rubber. Nanocomposites in isoprene rubbers are here examined. In a nutshell, these nanocomposites were prepared adopting the three methods summarized above and nano-silica was reported to promote the mechanical reinforcement of poly (isoprene) matrices, less that CB but more than conventional silica, with lower viscosity. 

Abstract This chapter describes the influence of three-dimensional nanofillers used in elastomers on the nonlinear viscoelastic properties. In particular, this part focuses and investigates the most important three-dimensional nanoparticles, which are used to produce rubber nanocomposites. The rheological and the dynamic mechanical properties of elastomeric polymers, reinforced with spherical nanoparticles, like POSS, titanium dioxide and nanosdica, were described. These (3D) nanofillers in are used polymeric matrices, to create new, improved rubber nanocomposites, and these affect many of the system s parameters (mechanical, chemical, physical) in comparison with conventional composites. The distribution of the nanosized fillers and interaction between nanofUler-nanofiUer and nanofiller-matrix, in nanocomposite systems, is crucial for understanding their behavior under dynamic-mechanical conditions. 

There are few reports on rubber-LDH nanocomposites in which they have been prepared mostly by solution intercalation methods and not by a conventional technique for processing rubber-based composites [102, 103]. But, the melt... 

NR composites and nanocomposites can be fabricated by three main techniques, namely latex compounding, solution mixing and melt blending. A variety of nanofillers, such as carbon black, silica, carbon nanotubes, graphene, calcium carbonate, organomodified clay, reclaimed rubber powder, recycled poly(ethylene terephthalate) powder, cellulose whiskers, starch nanocrystals, etc. have been used to reinforce NR composites and nanocomposites over the past two decades. In this chapter, we discuss the preparation and properties of NR composites and nanocomposites from the viewpoint of nanofillers. We divide nanofillers into four different types conventional fillers, natural fillers, metal or compound fillers and hybrid fillers, and the following discussion is based on this classification. 

The effectiveness of organoclay in NR was observed and reported by Carli et They evaluated the technical feasibility of NR nanocomposites with Cloisite 15A, a commercial organoclay to substitute conventional silica (Si02) filler. TEM analysis indicated that the OMt was homogeneously dispersed in the rubber matrix. A shift of the characteristic peaks to lower angles was observed in XRD, attributed to the intercalation of the OMt by macromolecular rubber chains. Based on the mechanical properties of the compounds they concluded that 50 phr of silica can be replaced by 4 phr of OMt with a reduction in the filler content by 12.5 times, without adversely affecting the tensile properties of the final material even after ageing. 

Micron-sized fillers, such as glass fibers, carbonfibers, carbon black, talc, and micronsized silica particles have been considered as conventional fillers. Polymer composites filled with conventional fillers have been widely investigated by both academic and industrial researchers. A wide spectrum of archival reports is available on how these fillers impact the properties. As expected, various fundamental issues of interest to nanocomposites research, such as the state of filler dispersion, filler-matrix interactions, and processing methods, have already been widely analyzed and documented in the context of conventional composites, especially those of carbon black and silica-filled rubber compounds [16], It is worth mentioning that carbon black (CB) could not be considered as a nanofiller. There appears to be a general tendency in contemporary literature to designate CB as a nanofiller - apparently derived from... 

DSC scans of the elastomer and its composites exhibit glass transition temperature (Tg), melting point and crystallinity. Melting temperature and Tg have not been affected either in presence of conventional filler or nanofillers while heat of fusion or crystallinity considerably decrease in CNT reinforced NR nanocomposite due to interaction between CNTs and rubber matrix [89]. On the other hand, poly... 

Burnside and Giannelis discussed the nanostructure-property relationships in polydimelhylsiloxane/LS nanocomposites. The solvent uptake in this nanostruc-tured silicon rubber was dramatically decreased when compared to conventional composites. Both swelling behavior and modulus were related to the excess amoimt of bonded rubber formed in the nanocomposites compared to conventional composites. 

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