Nano Carbon Black

To achieve a lower percolation threshold and a high conductivity, more than one type of filler with different dimensions can be used to prepare CPCs, such as zero-dimensional atomic clusters (e.g., nano-carbon black, and silica), ID rod-like nanofiller (e.g., carbon nanotubes, and silver nanowires), and 2D layered nanofiller (e.g., clay platelets, and graphene) [ 106-110]. In fact, because of their differences in shape and element component, each nanoparticle has its own unique ability. Positive synergistic effects of these nanoparticles on improving the electrical and other properties of polymer matrix are expected. 

Generally speaking, commercial rubber products are manufactured as a composite from a rubber and a nano-filler, which is in a group of fillers of nanometer size (mainly, carbon black and particulate silica). For an example, a pneumatic tire for heavy-duty usages such as aircrafts and heavyweight tracks is made from natural rubber (NR) and carbon black and/or silica. Their reinforcing ability onto rubbers makes them an indispensable component in the rubber products [1,2]. 

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. 

The morphology of the agglomerates has been problematic, although some forms of network-like structures have been assumed on the basis of percolation behavior of conductivity and some mechanical properties, e.g., the Payne effect. These network stmctures are assumed to be determining the electrical and mechanical properties of the carbon-black-filled vulcanizates. In tire industries also, it plays an important role for the macroscopic properties of soft nano-composites, e.g., tear. 

This fascinating product will still continue to develop to accommodate new applications, safety, health and environment (SHE) issues, advantages of novel materials like nano-composites, plasma-surface-modified carbon black, development of computer simulation techniques, and finally to develop a cybernetic or thinking tire. 

The morphology of the carbon was characterized by SEM and the particle size was determined by particle size analyzer. Figure 4 shows the SEM images of the carbon black. It was observed that the carbon black particles exhibit a sphere particle with nano-sized diameter. 

Filler, in general, can be defined as finely divided particles that are often used to enhance the performance and various desirable properties of the host matrix, depending on a typical application. A great deal of research endeavors have been dedicated to the development and the use of different fillers with a dimension at the nanometer level. In rubber technology the term nano is not unfamiliar to a rubber specialist. Since the start of the twentieth century, carbon black and silica have been utilized as effective reinforcing agents in various rubber formulations for a variety of applications. The primary particle sizes of these fillers remain in the nanometer range. However, with these conventional fillers the dispersion toward individual... 

Scientifically, the term ultrafine powder or ultrafine particles is used to describe solid products in which the particle sizes are no greater than 100 nm. The ultrafine white carbon black to be discussed in this chapter is the product of particles of a smaller size than those in common products, i.e., ultrafine here is not a scientific but a commercial term. The ultrafine powders in the scientific sense, e.g., nano copper, nano TiO and nano hydroxyapatite, and related topics will be discussed in later chapters. Nevertheless, the principles involved in the preparation of ultrafine white carbon black by impinging stream reaction-precipitation are very similar to those involved in the preparation of the nano powders mentioned above. Therefore this topic is discussed here under the overall title Preparation of ultrafine powders . 

In this chapter technical applications are described which are of utmost interest for mechanical and chemical engineers working with particles in the nano size regime. These are the control of production processes of carbon blacks and of non-carbonous and metallic particles, the characterization of soot in automotive applications and the investigation of in liquids suspended particles. 

Time-Resolved Laser-Induced Incandescence (by Prof. Alfred Leipertz et al.) introduces an online characterization technique (time-resolved laser-induced incandescence, TIRE-LII) for nano-scaled particles, including measurements of particle size and size distribution, particle mass concentration and specific surface area, with emphasis on carbonaceous particles. Measurements are based on the time-resolved thermal radiation signals from nanoparticles after they have been heated by high-energetic laser pulse up to incandescence or sublimation. The technique has been applied in in situ monitoring soot formation and oxidation in combustion, diesel raw exhaust, carbon black formation, and in metal and metal oxide process control. 

Nano-sized PtRu catalysts supported on carbon have been synthesized from inverse micro emulsions and emulsions using H2PtClg (0.025 M)/RuCl3 (0.025 M)/NaOH (0.025 M) as the aqueous phase, cyclohexane as the oil phase, and NP-5 or NP-9) as the surfactant, in the presence of carbon black suspended in a mixture of cyclohexane and NP-5-I-NP-9 [164]. The titration of 10% HCHO aqueous solution into the inverse micro emulsions and emulsions resulted in the formation of PtRu/C catalysts with average particle sizes of about 5 nm and 20 nm respectively. The RuPt particles were identified by X-ray diffraction. X-ray photoelectron, and BET techniques. All of the catalysts prepared show characteristic diffraction peaks pertaining to the Pt fee structure. XPS analysis... 

CanadlndsLtd, CanP 658221 and Kemixon Reporter, October 1963, p 1168, Item 10—614—3 [Explosives in suspension such as AN 37.5, NaNO 24.5, TNT (in pieces) 25-0 carbon black 1.0 suspended in 12.0 parts water)... 

This is where the synthesis of nano-sized molecular sieves is carried out in the template matrix within confined spaces. This is an ideal synthetic route if the space size and uniformity favor the crystallization, and the as-synthesized product is easily isolated from the templates. Mesoporous molecular sieves with uniform mesopore structures can be adopted as the template, such as MCM-41. In 2000, Schmidt et al.[127] first proposed such a route to synthesize ZSM-5 nanocrystals. The synthesis procedure consisted of the impregnation of mesoporous carbon black with reaction solution, followed by treatment with steam at 150 °C, and the combustion of carbon black. Compared with other methods, the advantage of this one is that the nano-sized product is easily isolated and the yield is relatively higher. However, it also has some drawbacks. First, there is a high requirement for the preparation of carbon black as the template matrix, i.e., the mesopore sizes in carbon black must be uniform. Second, the crystallization must be performed in the mesopores, not on the extra surfaces of the carbon black. Third, a large amount of carbon black will be consumed (about four-times that of the nanozeolite product). All of these factors affect the further development of this route to some degree. 

There has been a trend in recent years to move towards the electrostatic deposition of paints for exterior automotive applications. Reasons for this include improved paint transfer efficiency. Normally, plastic parts need to be painted with a conductive primer prior to the electrostatic painting of base and clear coats. One of the most recent developments in the area of external automotive applications is that of intrinsically conductive resins for electrostatic painting. Currently there are commercial applications for body panels that utilize PPE/PA that contains carbon black as the conductive component. In the USA, a mirror shell application uses PPE/PA where the conductivity is achieved through the incorporation of graphite nano-tubes. 

Polymer blends for packaging and materials handling of electrical components would require a degree of electrical conductivity to provide for static charge dissipation. This can be achieved either by a conductive additive, such as carbon black, carbon nano-tubes or metal fibers, or via blending with a conductive polymer like polyanUine. Blending of the latter is necessary to provide flow... 

L. Li, W. Zhu, P. Zhang, Z. Chen, W. Han, Photocatalytic oxidation and ozonation of catechol over carbon-black-modified nano-Ti02 thin films supported on A1 sheet . Water Research, 37 (15) 3646-3651, (2003). 

The data in the table, as specified by the manufacturers, show that graphite particles are mostly of micron sizes (from 10 to 28 pm) and have a specific surface area from 9 to 24 m g. Carbon blacks comprise nano-sized particles (from 12 to 100 nm) and their specific surface area varies from 45 to several hundreds and even over thousand, of square meters per gram. Because of these differences in size and surface area of the various carbon and graphite... 

But PVC forms many composite materials with particulate and fibrous fillers. Cellulose fiber and newsprint recycled fiber are two common examples of fibrous materials. The list of powders is longer, including talc, mica, clay, wood flour, carbon black, glass beads, hydrotalcite, alumina trihydrate, polypyrrole, and various nano-materials including nano-calcium carbonates. 

The effects of nano-structured carbon fillers [fuUerene C60, single wall carbon nanotube (SWCNT), carbon nanohom (CNH), carbon nanoballoon (CNB), and ketjenblack (KB) and conventional carbon fillers [conductive grade and graphi-tized carbon black (CB)]] on conductivity (resistance), thermal properties, crystallization, and proteinase K-catalyzed enzymatic degradation of PLA films were investigated by Tsuji et al. [70]. The researchers found that the addition of 1 wt% SWCNT effectively decreased the resistivity of PLA film compared with that of conventional CB. The crystallization of PLA further decreased the resistivity of films. The addition of carbon fillers, except for C60 and CNB at 5 wt%, lowered the glass transition temperature, whereas the addition of carbon fillers, excluding... 

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