Sodium dodecyl benzene sulfonate effect

While raising the pH gave some improvements in lather, more improvement was needed. Various co-surfactants, including alkyl sulfates, alkyl aryl sulfonates, and fatty acid taurides were effective in improving the speed of lather when present at levels of around 5%. Cost considerations led to choosing an alkyl aryl sulfonate, particularly sodium dodecyl benzene sulfonate, as it was already widely used in the formulation of laundry detergents. 

Various detergents were examined for their effect on lather properties. It was observed that alkyl aryl sulfonates (like sodium dodecyl benzene sulfonate) and alkyl sulfates (like sodium lauryl sulfate) had the biggest impact as foam boosters. This is not surprising, as both surfactants have head groups with high charge density, which is important for achieving rapid and stable foam [20],... 

Addition of sodium dodecyl benzene sulfonate to dilute alkaline electrolyte depresses the passivation of zinc surface [275]. Owing to the dodecyl benzene sulfonate adsorption, the passive layer on zinc has a loose and porous structure. Zinc electrodissolution was inhibited by the presence of sodium metasdicate [276] and some acridines [277]. The protection effect was described by a two-parameter equation. 

It thus seems that sodium dodecyl sulfate, sodium tetrapropylene benzene sulfonate, and potassium octadecanoate do accelerate the thermal initiation reaction of styrene but that Triton X-100 and sodium dodecyl benzene sulfonate do not although the latter is effective in accelerating thermal initiation of alkyl methacrylates (3 ). ... 

This glycol-AN explosive like the methanol and ethanol compositions are very efficient. Since the glycols and glycerins are in effect forms of alcohols, they perform similarly. Glycerin could be substituted for the glycol, but it s cost is even higher than glycol. Addition of a small amount of "Tide" or "Mr. Bubble" (e g. sodium dodecyl benzene sulfonate) will increase the performance and detonation rate by 15-35%. 

For solutions of typical ionic surfactants with no added salts the studies of Carroll and Ward showed that solubihzation rates were much smaller than those for nonionic surfactants, presumably because the surfactant ions adsorbed at the oil-water interface repelled the micelles of like charge in the solution. Indeed, Bolsman et al. found no measurable solubilization of n-hexadecane into solutions of a pure benzene sulfonate and a commercial xylene sulfonate. They injected small oil drops into the surfactant solutions and observed whether the resulting turbidity disappeared over time due to solubilization. Similarly, Kabalnov found from Ostwald ripening experiments that the rate of solubilization of undecane into solutions of pure SDS was independent of surfactant concentration and about the same as the rate in the absence of surfactant. That is, the hydrocarbon presumably left the bulk oil phase in this system by dissolving in virtually miceUe-free water near the interface. In similar experiments TayloC and Soma and Papadopoulos observed a small increase in the solubilization rate of decane with increasing SDS concentration. De Smet et al., who used sodium dodecyl benzene sulfonate, which does not hydrolyze, found, like Kabalnov, a minimal effect of surfactant concentration. 

Fig. 5. Toluene displacing 500 ppm sodium dodecyl benzene sulfonate solution effect of velocity.

Use of surfactants is an effective way for dispersing CNTs [39]. Reports show that the outer most nanotubes in a bundle are treated more than the innermost tubes and the nanotube remains predominantly btmdled even after surfactant treatment. But mechanical methods like ultrasonication can debundle the nanotubes by steric or electrostatic repulsions [40]. On sonication the high local shear will unravel the outer carbon nanotubes in a bundle and expose other sites for additional surfactant adsorption, thus the surfactant molecules gradually exfoliate the bundle in an unzippering mechanism [41]. Some of the common surfactants used for the dispersion of carbon nanotubes are sodium dodecyl benzene sulfonate (SDBS) [42], dodecyl trimethyl ammonium bromide (DTAB) [43], hexadecyl trimethyl ammonium bromide (CTAB) [44], octylphenol ethoxylate (Triton X-100) [45] and sodium dodecyl sulfate (SDS) [46]. Covalent modification is another way to solubilize the CNTs in different solvents and to improve the interaction with the matrix in composites [47]. 

The linear alkyl benzene sulfonates (LABS) are manufactured from alkyl benzene and the alkyl chain length can vary from Cg to C15 and their properties are mainly influenced by the average molecular weight and the spread of carbon number of the alkyl side chain. The CMC of sodium dodecyl benzene sulfonate is 5 x 10 mol dm (0.18%). The main disadvantages of LABS is their effect on the skin and hence they cannot be used in personal care formulations. 

The results are shown in Figure 27. It can be seen the all the anionics tested show significant effects of the combination with SAE on their sequestering ability. For this effect, the optimum EO mole number for each anionic is different. Since the combination of LAS with STPP gives a calcium ion sequestering ability of only 165 mg/g-detergents by this procedure, the combination of SAE with LAS(Linear Alkyl-benzene Sulfonate), AOS (4-Olefin Sulfonate), SAS(Secondary Alkane Sulfonate) or SDS (Sodium Dodecyl Sulfate) would be recommended for use in heavy-duty detergents. 

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