Nanofillers carbon black

D-TEM gave 3D images of nano-filler dispersion in NR, which clearly indicated aggregates and agglomerates of carbon black leading to a kind of network structure in NR vulcanizates. That is, filled rubbers may have double networks, one of rubber by covalent bonding and the other of nanofiller by physical interaction. The revealed 3D network structure was in conformity with many physical properties, e.g., percolation behavior of electron conductivity. 

Filler Carbon black Natural amorphous silica, precipitated silica, nonblack nanofiller Solvent Organic solvent Aqua-based solvent... 

Where a is the composite conductivity, a0 a proportionally coefficient, Vfc the percolation threshold and t an exponent that depends on the dimensionality of the system. For high aspect ratio nanofillers the percolation threshold is several orders of magnitude lower than for traditional fillers such as carbon black, and is in fact often lower than predictions using statistical percolation theory, this anomaly being usually attributed to flocculation [24] (Fig. 8.3). 

The recognition of the unique properties of carbon nanotubes (CNTs) has stimulated a huge interest in their use as advanced filler in composite materials. In particular, their superior mechanical, thermal and electrical properties are expected to provide much higher property improvement than other nanofillers (18-22). For example, as conductive inclusions in polymeric matrices, CNTs shift the percolation threshold to much lower loading values than traditional carbon black particles. 

The pol5mier nanocomposite field has been studied heavily in the past decade. However, polymier nanocomposite technology has been around for quite some time in the form of latex paints, carbon-black filled tires, and other pol5mier systems filled with nanoscale particles. However, the nanoscale interface nature of these materials was not truly understood and elucidated until recently [2 7]. Today, there are excellent works that cover the entire field of polymer nanocomposite research, including applications, with a wide range of nanofillers such as layered silicates (clays), carbon nanotubes/nanofibers, colloidal oxides, double-layered hydroxides, quantum dots, nanocrystalline metals, and so on. The majority of the research conducted to date has been with organically treated, layered silicates or organoclays. 

Nanofillers have actually been around for decades (the oldest for over a century) carbon blacks, pigments, precipitated silicic acid (Ultrasil, Degussa-Hiils), pyrogenic silicic acids (Aerosile, Degussa-Hiils), phyllosilicates, nucleation agents, reactive silicone nanoparticles for epoxy resins, ceramic materials and inorganic-organic hybrid particles from sol-gel transformations, for example synthetic, dispersible aluminate (boehmite) powder. 

NanofiUers are often added to enhance one or more of the properties of polymers. Inactive fillers or extenders raise the quantity and lower the cost price, while active fillers bring about targeted improvements in certain mechanical or physical properties. Common nanofillers include calcium carbonate, ceramic nanofiUers, carbon black, carbon nanotubes (CNTs), carbon... 

This is Volume 2 of Natural Rubber Materials and it covers natural rubber-based composites and nanocomposites in 27 chapters. It focuses on the different types of fillers, the filler matrix reinforcement mechanisms, manufacturing techniques, and applications of natural rubber-based composites and nanocomposites. The first 4 chapters deal with the present state of art and manufacturing methods of natural rubber materials. Two of these chapters explain the theory of reinforcement and the various reinforcing nanofillers in natural rubber. Chapters 5 to 19 detail the natural rubber composites and nanocomposites with various fillers sueh as siliea, glass fibre, metal oxides, carbon black, clay, POSS and natural fibres ete. Chapters 20-26 discuss the major characterisation techniques and the final ehapter covers the applications of natural rubber composites and nanoeomposites. By covering recent developments as well as the future uses of rubber, this volume will be a standard reference for scientists and researchers in the field of polymer chemistry for many years to come. 

In the previous paragraphs, carbon nanofillers such as nanotubes and graphite nanoparticles were examined. An intriguing carbon nanofiller is undoubtedly nano-CB. A preliminary crucial aspect is to define the meaning of nano-CB. By considering the diameter of primary particle, most carbon blacks could be classified as nano-CB, " as it is shown in Table 2.7. In fact, as mentioned in the Introduction, according to the acknowledged definition, a nanoparticle should have at least one dimension of the order of 100 nm or less . However, it was... 

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. 

A large-scale application of rubber nanocomposites, such as the one in the tyre industry, reasonably implies the use of hybrid filler systems, with a minor amount of nanofiller added to a major part of a traditional filler, such as silica or carbon black. 

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... 

The words nanocomposites and nanofillers are fairly recent, but have been in use since 1904 for example, carbon black is being used as a reinforcing filler in rubbers and apparently always existed in nature (in minerals and vegetation) [1, 2]. 

Carbonaceous Nanofillers Recently research efforts have focused on nano-scale variants of carbon black (carbon nanotubes, carbon nanofibers and exfoliated nanographite) as possible reinforcing fillers in elastomers. Among these, nanotubes are attracting the most attention. 

In some cases, the polysiloxane was in the form of a composite—for example, with sulfonated cross-linked polystyrene particles, carbon black,acrylate latexes,or sodium dodecyl sulfate. Counterintuitively, the addition of impenetrable nanofillers can actually increase the permeability of a membrane. Also, siloxane-imide copolymers have shown some interesting properties in membrane separations, as have polysiloxanes containing poly(ether amine) groups. ... 

During the past three decades, many research works have shown a significant improvement in the gas barrier properties of nanofiller reinforced polymer membranes (Espuche, 2011). It was demonstrated that the adding of nanofillers (layered clays, carbon blacks or nanotubes, etc.) into a polymer matrix increases significantly the tortuosity of diffusion paths. Unfortunately, this physical way of external stabilization is still often ignored by practitioners. 

Fig. 4 TEM images of the nanofillers (a) carbon black, (b) SWCNT (c) DWCNT (d) amino-functionalized doublewall CNT (e) MWCNT and (f) amino-functionalized MWCNT [51]...

There are various types of carbon nanofillers which include carbon black, multi walled carbon nanotubes (MWCNTs), and single walled carbon nanotubes (SWCNTs) [27]. In this section the effect of these nano fillers on viscoelastic behavior is thoroughly discussed. The physicomechanical properties of conductive carbon black (CCB) filled ethylene acrylic elastomer (AEM) vulcanizates have been reported by B.P. Sahoo et al. They have discussed thoroughly about the effect carbon black concentration on the viscoelastic behavior of CCB-AEM nanocomposites with respect to temperature variation. Figure 10a, b represents the variation of storage modulus and loss modulus with temperature. It is observed that the value of storage modulus (E ) increased with increase in filler loading in the... 

---