Micelles anionic-nonionic mixed, solubilization

Mixed Anionic-Nonionic Micelles An investigation of the solubilization of Yellow OB by mixed micelles of anionics and a POE nonionic, Q 2 5(002114)9-OH, indicated that increased solubilization of the dye occurs when there is interaction between the POE chain and the benzenesulfonate groups,... 

The target HLB can be obtained by using a mixture of anionic surfactant (HLB = 9.4) and nonionic surfactant HLB = 16.7) in the right proportions (1 3.75 based on the formula in Table 3). Such mixing of anionic and nonionic surfactants is expected to lower the individual CMC s and thus an increase of the soil solubilization capacity. The surfactants in the product should be in spherical micelle phase to give a transparent/translucent appearance and small viscosity (Table 6). 

In this paper, we report the solution properties of sodium dodecyl sulfate (SDS)-alkyl poly(oxyethylene) ether (CjjPOEjj) mixed systems with addition of azo oil dyes (4-NH2, 4-OH). The 4-NH2 dye interacts with anionic surfactants such as SDS (11,12), while 4-OH dye Interacts with nonionic surfactants such as C jPOEn (13). However, 4-NH2 is dependent on the molecular characteristics of the nonionic surfactant in the anlonlc-nonlonic mixed surfactant systems, while in the case of 4-OH, the fading phenomena of the dye is observed in the solubilized solution. This fading rate is dependent on the molecular characteristics of nonionic surfactant as well as mixed micelle formation. We discuss the differences in solution properles of azo oil dyes in the different mixed surfactant systems. 

Interaction between the surface-active components in surfactant mixtures and with the solubilizate can both increase and decrease solubilization into the mixed micelles. Thus, the addition of small quantities of sodium dodecyl sulfate sharply decreases the solubilization of Butobarbitone by micellar solutions of a commercial POE nonionic, Ci2H2s(0C2H4)230H. The competitive interaction of the sodium dodecyl sulfate with the oxyethylene groups on the surface of the micelles of the nonionic surfactant is believed to be the cause of this phenomenon (Treiner, 1985). On the other hand, a mixture of sodium dodecyl sulfate and sorbitan monopalmitate in aqueous solution (Span 40) solubilized dimethylaminoazobenzene more than either surfactant by itself, with maximum solubilization observed at a 9 1 molar ratio of the anionic to the nonionic (Fukuda, 1958). 

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