Graphon 2 carbon

The system described in this investigation is polystyrene-14C adsorbed on Graphon carbon black (graphitized Spheron 6) from six solvents comprising a wide spectrum from good to poor solvent power. Well-characterized materials were selected to elucidate the conformation of polymer molecules at the solid/liquid interface. So far two models have been postulated to describe the conformation of the adsorbed polymer molecules at the solid/liquid interface (9, 13, 14, 18, 19, 21, 27). In the first model the polymer assumes a loop or coil structure in which only a fraction of the polymer segments are attached directly at the interface, and in the second model the polymer forms a relatively flat and compressed interfacial layer with many segments attached to the solid substrate. 

Figure 1 High resolution 100 Mhz spectrum of PEO750 in a Graphon/carbon tetrachloride dispersion, showing both the methylene and methyl protons.

Mogul carbon black of Mogul carbon black of Mogul-A carbon black Mogul-A carbon black ELF-O carbon black of ELF-O carbon black of Spheron-6 carbon black Spheron-6 carbon black Graphon carbon black of Graphon carbon black... 

Phillips R, Vastola FJ, Walker Jr. PL. Thermal decomposition of surface oxides formed on Graphon. Carbon 1970 8(2) 197-203. 

Figure 40 Low-resolution Raman spectrum of graphon (exciting line, 514.5 nm Ar", 240 mW, rotating cell, 3000 rpm) [117]. (Reproduced from Carbon 22, Mernagh, T. R, et al., Raman spectra of graphon carbon black, pp. 39-42. Copyright 1984, with permission from Elsevier Science.)...

Fig. XVn-21. (a) Differential heat of adsorption of N2 on Graphon, except for Oand , which were determined calorimetrically. (From Ref. 89.) (b) Differential heat of adsorption of N2 on carbon black (Spheron 6) at 78.5 K (From Ref. 124).

Fig. 2.25 The differential heat of adsorption of argon on carbon blacks at 78 K, before and after graphitizalion.. Spheron O, Graphon. , and El denote molar heat of sublimation and of evaporation respectively.

Fig. 4.2 Equilibrium adsorption of sodium n-dodecyl sulfate on carbon black, Ti02, and Graphon at room temperature [41].

Figure Ic differs markedly from those obtained for the immersion of polar solids in water initially the heat values are small but increase with increasing amounts of preadsorbed water. Thus far, only one such curve has been reported in the literature for the system Graphon-water 90). Graphon is a graphitized carbon black which has an essentially homogeneous, homopolar surface 21). Nevertheless, a small fraction of heterogeneous sites is responsible for the limited adsorption of water on the surface of this solid. Similar curves can be expected for other hydrophobic solids.

Heats of immersion provide a new tool for rating the wetting ability of surfactants from aqueous solution. If a high-area graphite, Graphon, or carbon black is used, the increased heat effect obtained with the surfactant solution over that obtained with water allows the wetting tendency of the surfactant to be rated (71). Typical heats of immersion in surfactant solutions are listed in Table IX. 

Pierce and Smith (56) have observed a Type III isotherm for water vapor on a highly graphitized carbon black (graphon, 80 square meters per gram) at 28.9° C. They suggest that water vapor adsorption occurs only on the most active sites and that the entire surface is probably never covered. 

The adsorption isotherms for carbon black and graphitised carbon black (graphon) are completely different. For graphitised carbon black a step-like adsorption isotherm is... 

Graphon black, kindly furnished by the Cabot Corporation, was the adsorbent and its physical properties are listed in Table I. The term Graphon refers to Spheron 6 which had been heated to 2,700°-3,200°C. This graphitized nonporous carbon black is a unique form of carbon with uniform surface and high surface area. The Graphon samples were dried for 12 hrs. at 140°C. and stored in vacuo before use in the adsorption experiments. 

In the presence of H20 between 652 and 852°C, Pt is more efficient than other metals or oxides (149) in the gasification of Graphon, Sterling F-T, and Norit-A carbons. Since the reaction products are CO + H2 (and only CH4 if the gasification is carried out in H2), the spiltover species may be the products of dissociation of H20, probably H, O, and OH. 

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