Carbon black carboxyl group

Carbon black has been reported to possess different kinds of surface chemical groups. These are aromatics, phenol, carboxylic, etc. The different sites can be estimated by comparing the adsorption characteristics of different adsorbents (such as hexane and toluene). 

Carbon blacks have been reported to be capable of initiating the cationic polymerization of vinyl monomers such as vinyl ethers, indene, and acenaphthylene. The grafting sites of the polymer were based on carboxyl groups present on the surface [88]. The polymerization was inhibited by treatment of the carbon blacks with NaHCOs, CH2N2, pyridine, and DMF. Also, the degree of conversion was found to be dependent on temperature and time of polymerization [89]. 

It appears from the evolution of the adhesion index that a distinction has to be made between the interactions carbon blacks are able to have with unsaturated or with saturated (or near-to-saturated) elastomers. Thus, the adhesion index of butyl rubber is enhanced upon oxidation of the black, while the reverse is observed with polybutadiene 38). The improvement of the reinforcing ability of carbon black upon oxidation, in the former case, has been interpreted by Gessler 401 as due to chemical interactions of butyl rubber with active functional groups on the solid surface. Gessler, relating the reinforcing characteristics of the oxidized carbon black for butyl rubber to the presence of carboxyl groups on the surface of the filler, postulated a cationic... 

Figure 2.3 In a polypeptide of five amino acids, the bold black C is the alpha carbon. The amino acids are linked together by a peptide bond (red atoms) linking the carboxylic group of one amino acid to the amino group of the next amino acid. The R group (blueR) can be any sidechain. The Ca-C-N-Ca-C-N-CQ-C-N is the "backbone."...

PAS-FTIR spectra have been used to find out the interaction of chlorosulphonated polyethylene (CSM) and carbon black N110 [48]. A number of bands in the 1800 cm1-1680 cm1 region in the spectrum of Nil0 (Figure 2.7) confirm the presence of different carbonyl functionalities, which may include carboxyl group, lactone and quinone. The band at 1651 cm1 is characteristic of aromatic double bonds in the carbon black. The... 

The main difference between two grades of carbon black is the presence of carboxylic acid groups at 1717 cm1 for oxidised carbon black. 

The functional groups present in charcoal are phenols, carboxylic acids, quinones, ketones and lactones. They are essentially acidic supports. The nature and extent of the functionalities on the charcoal particle surface are a function of the material used in the carbonization and the type and duration of the activation procedure. In addition, treatment of these charcoals with oxidizing agents such as nitric acid or hydrogen peroxide increases the number of acid species present. A similar treatment will also functionalize the non-porous carbon blacks.25 Because of this it is difficult to draw any general conclusions concerning the adsorption capabilities of these charcoals other than to say that being acidic they will most readily adsorb cationic species. 

Carbon-Oxygen Surface Complexes. The importance of surface complexes in the behaviour of carbon blacks has been reflected in several surveys of the field. " Generally, the existence of carboxylic, phenolic, and carbonyl type groups is accepted, although there is strong evidence that some combined structures involving numerous mesomeric forms, is a more accurate representation of the true situation. It is rewarding to consider briefly work in the field beyond that reported in the above reviews. " ... 

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