Sodium dodecylbenzene sulphonate

Fig. 7.1 shows the trace obtained from the analysis of undegraded linear alkylbenzene sulphonate (LAS) mixture (sodium dodecylbenzene sulphonate). Peak identifications were made by co-injection with pure undegraded linear alkylbenzene sulphonate compounds and confirmed by analysis of the undegraded linear alkylbenzene sulphonate mixture by desulphonation followed by gas chromatography of the resultant alkylbenzenes on a 15m OV-1 support coated open-tubular column. 

An example of the separation of the anilides of the eight lowest straight-chain carboxylic acids on sodium dodecylbenzene sulphonate is shown in Fig. 5.14. The problem of the procedure described above consists in that formanilide cannot be prepared as CO, SO2 and HC1 are produced by the action of thionyl chloride on formic acid. Formanilide must, therefore, be prepared in an aqueous medium, the other acids must be extracted into a non-aqueous medium. The yield of the extraction varies considerably depending on the type of the acid, and the presence of water in the reaction medium may affect the reaction yield significantly, which makes quantitative analysis difficult. Condensates with toluidine, which were used for the determination of formic acid by GC, are prepared by an analogous procedure. As other toluidine isomers may serve as the reagents, formyl derivatives have been suggested for the separation of these substances [181]. 

Fig. 5.14. Separation of anilide derivatives of Cj -Cs straight-chain carboxylic acids. Peaks 1 = propionic 2 = n-butyric 3 = acetic 4 = n-valeric 5 = n-hexanoic 6 = formic and n-heptanoic 7 = n-octanoic acid STD = methyl myristate. Conditions glass column, 12 ft. x 3 mm I.D., 2.5% (w/w) sodium dodecylbenzene sulphonate on Chromosorb G (60-80 mesh, NAW) nitrogen inlet pressure, 15 p.s.i. temperature, 200°C. (Reproduced from/. Chromatogr., 51 (1970) 147.)...

This is evidenced by the values of pressure at which the CBF/NBF transition in NaDoS films occurs, n 9-104 Pa, since for sodium dodecylbenzene sulphonate films n is from 2 to 4104 Pa. Furthermore, the film radius in the latter case is larger, which can impede the precise identification of the metastable region of CBF/NBF transition (see Section 3.4.2). 

The purpose of this paper is to give a brief summary of an Investigation which has been carried out into the aqueous-phase polymerisation of butadiene initiated by cobalt(III) acetylacetonate In the presence of surfactants such as sodium dodecylbenzene-sulphonate and sodium decyl sulphate. It is Intended that fuller details of the investigation will be published elsewhere in due course. 

The polymerisation rate depends very much upon the nature of the surfactant used. In particular, reaction occurs more readily in the presence of sodium dodecylbenzene-sulphonate than in the presence of potassium oleate. 

Effect of surfactant level. Much of the earlier work on this reaction system was carried out using sodium dodecylbenzene-sulphonate as the surfactant. In the course of experiments which were Intended to investigate the effect upon polymerisation rate of varying the surfactant level, it was discovered that purified sodium dodecylbenzenesulphonates are apparently able to act as initiators of free-radical emulsion polymerisation in the absence of other added Initiating substances. Furthermore, as the results summarised in Figure 5 show, the rate of polymerisation in the absence of added initiator is directly proportional to the concentration of sodium dodecylbenzenesulphonate In the aqueous phase. 

An International Symposium on Mining Research took place in 1961 (60) and was partly dedicated to AN—FO explosives. Hino and Yokogawa (61) described the action of sur/actants on the detonation ability of ammonium nitrate and its mixtures with coal tar in proportions 93.3/6.2- The addition of 0.55 of surfactant increased the detonation ability of the mixtures. Particularly effective were sodium dinaphthylmethane disulphonate, sodium laurylsulphon-ale and sodium dodecylbenzene sulphonate. 

Lee, H.-H. et al.. Dispersion of Fe3O4 suspensions using sodium dodecylbenzene sulphonate as dispersant. Mater. Lett., 61, 3974, 2007. 

An alternative anionic wetting agent is sodium dodecylbenzene sulphonate, with a branched alkyl chain... 

Dejing G, Na H, Yuan T, et al. Determination of bovine serum albumin using resonance light scattering technique with sodium dodecylbenzene sulphonate-cetyltrimethylammonium bromide probe. Spectrochim Acta A Mol Biomol Spectrosc 2007 3 573-7. 

Household detergents may contain 20-50% sodium triphosphate, together with comparatively small amounts of a long (carbon)-chain surface active agent such as sodium dodecylbenzene sulphonate,... 

Sodium dodecylbenzene sulphonate Surface active agent 10... 

Makowska, D., Sobczynska, A., Zimoch, J., Szymanowski, J. 2001. Interfacial activity of ethoxyethyl-ated fatty acid methyl esters. Mixtures with sodium dodecylbenzene sulphonate. Proceedings XXXI Jornadas Anuales del CID. Barcelona, 325-336. 

An interesting feature of the adsorption curves of many ionic surfactants is the occurrence of a distinct maximum in the isotherm at concentrations well in excess of the CMC. Such curves have been reported for the adsorption of sodium dodecyl sulphate and potassium myristate on graphite [60], sodium dodecyl sulphate on cotton and carbon [61,62] and sodium dodecylbenzene sulphonate on cotton, nickel and lead [63]. The striking decrease in the adsorption of sodium tetradecyl- and dodecyl sulphate on to porous glass (Fig. 1.11) at high concentra-... 

A solution of hydroxy ethyl cellulose is made in de-ionised water. To this solution is added the sodium dodecylbenzene sulphonate, ammonium acetate and ammonium persulphate. 

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