Graphitized black

FIGURE 22.8 Payne effect (left) and stress-strain curves right) of solution-based styrene-butadiene rubber (S-SBR) composites with fixed amounts of carbon black N220 and graphitized black N220g, as indicated. (From Kluppel, M. and Heinrich, G., Kautschuk, Gummi, Kunststoffe, 58, 217, 2005. With permission.)... 

Black phosphorus may be either amorphous or crystalline. It exhibits quite low reactivity, both with oxygen and other reagents, compared to white or red phosphorus, and is stable in air. Because it has a puckered shape, the phosphorus remains tricoordinated in black phosphorus and crystallizes in sheets in a way similar to the behavior of graphite. Black phosphorus is generated from white phosphorus either by heating under pressure or in the presence of mercury. It is of relatively little value for the synthesis of organophosphorus compounds. 

Haberstroh, P. R., Brandes, J. A., Gelinas, Y., Dickens, A. F., Wirick, S., and Cody, G. (2006). Chemical composition of the graphitic black carbon fraction in riverine and marine sediments at submicron scales using carbon X-ray spectromicroscopy. Geochim. Cosmochim. Acta 70,1483-1494. 

Fig. 7 Yardstick-plots (Eq. 1) of the graphitized black N220g obtained with a series of alkenes (ethylene, propylene, iso-butylene) (filled symbols) and alkanes (ethane, propane, iso-butane) (open symbols). Adsorption temperatures are chosen as evaporation points at vapor pressures p0 103 mbar (lower curves) and po 104 mbar (upper curves) of the condensed gases, respectively...

The results for the surface fractal dimension of a series of furnace blacks and graphitized blacks, obtained by nitrogen adsorption in the multilayer regime, are summarized in Fig. 11. The cut off lengths are quite similar... 

Fig. 11 Surface fractal dimensions ds on atomic length scales of furnace blacks and graphitized blacks in dependence of specific surface. The data are obtained from nitrogen adsorption isotherms in the multilayer regime...

Graphitized black 48, 50, 60 -, furnace black 17 Growth, disorderly 2, 8... 

Other recent work (Hess and Herd, 1993) on the microstructure of carbon blac] confirmed earlier findings (Medalia and Rivin, 1976) that the particles of some pa graphitized blacks are composed of hollow graphitic shells. Thus, voids are fom the interior of the particles and agglomerates as a result of localized densificatioi... 

Figures 2-4 show substantial, though various or individual test compounds drop of heat of adsorption values caused by the addition of very small amount (about 2% mass) of PEG 4000 when PEG 4000 amount on the carbosil surface is higher the relationship becomes more complex. Extremes occur on the plots of the investigated relationships q = f(%PEG) in a similar way as in the case of graphitized black covered with PEG 1500 [44,45]. The occurrence of maxima and minima on the discussed type of plots was explained by the authors of the referred papers by formation of successive monolayers of liquid phase on the surface of carbon adsorbent. From the above and the well known [26,30,35] fact that heats of adsorption are usually higher on carbosils than on the non-modified surface of silica gel one would expect that the first portions of PEG 4000 are adsorbed on the surface of carbosil carbon patches. The fact that pores can on the surface of non-modified silica are narrower than on a carbosil surface [27] seems to confirm such a conclusion indicating reduction of adsorption site number on the silica surface. Thus the sequence of liquid phase deposition would be the following first on the carbon patches and then on the uncovered silica surface.

Interaction energies (heats of adsorption) of test compounds on carbosil change in a. sequence characteristic of graphitized blacks [43] with which the compounds interact in a non-specific way q > q°t,B- That is why higher values of a were obtained in case of silica gel. PEG deposition on silica surface, however, causes selectivity decrease whereas the coefficient a increases on carbosil modified with glycol (Table 1). A considerable increase is observed after polyethylene glycol monolayer formation on the complex adsorbent surface. 

Similar data (not shown (2j6)) for the graphitized black, Graphon, exhibits little evidence for significant interaction with either white reference solid. 

Cotten and Boonstra (150) also investigated stress relaxation in swollen vulcanizates. In these experiments, very near elastic equilibrium, n was found to be of the order of 0.01 or less for unfilled vulcanizates and vulcanizates filled with graphitized black. For rubbers reinforced with fully reinforcing furnace black n was two to three times the value for the unfilled rubber. The additional relaxation appears to be due to slow desorption of polymer segments held relatively tightly at the filler surface. 

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