A Microemulsion Cosurfactant With Excellent Water Solubilization at High Oil Content

Some examples of systems including useful ingredients as cosurfactants and cosolvents to furnish suitable microemulsions to be applicated in technological fields such as cosmetics and dermopharmaceuticals, are given. For systems with ionic surfactants, the usual cosurfactant (medium chain lenght alcohol) was substituted by more skincompatible ingredients as butyl lactate, or alternatively by oleic acid and a glycol as cosolvent mixedin the aqueous phase of the system. On the other hand, for a system with an alkyl glucoside as nonionic surfactant, temperature -insensitive microemulsions was obtained also with butyl lactate as cosurfactant. Moreover, the influence that the presence of glycols as cosolvents involve on the isotropic liquid regions of such systems has been also evidenced. In conclusion, it is possible to formu1ate suitable microemulsions to practicalapplications, overcoming the traditional problems of the most of the conventional microemulsions as are the biological agressivity of the cosurfactant for ionic surfactant systems, and the temperature dependence for nonionic surfactant systems.

Section: Introductionmentioning

confidence: 97%

Alternative Cosurfactants and Cosolvents to Prepare Microemulsions Suitable for Practical Applications

Comelles

1999

“…As the surfactant concentration decreases, the optimum salinity increases obviously to make a rigid interlace and to decrease the natural radius [9,lOj and thus to form micoremulsions. Hexylarnine [7,8] and glycol ether [15][16][17] has been reported to be a very effective cosurfactant giving rise to high solubilization of oil and water at low concentrations of an ionic surfactant (e.g. SDS or CTAB) and the cosurfactant.…”

Section: Introductionmentioning

confidence: 99%

“…So in this work, some observations on the phase diagrams of sodium oleate(SO) and cetyltrimethylammonium bromide (CT AB) and alcohols such as ipentanol, n-hexanol and n-octanol in two volumes of diesel oil and one volume of water are presented. The phase behavior of both the SO microemulsion and CTAB microemuision systems is well established, and a considerable number of studies of multiphase systems where they intervene have also been presented (50 [9,10,12], CTAB [5,7,8]). …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Formation and Phase Behavior of Water-in-Diesel Oil Microemulsion With Sodium Oleate and Cetyltrimethylammonium Bromide

Zhao

Lin

et al. 1996

The phase behavior and solubilization of multiphase microemulsions in mixed anionic-cationic surfactant systems were studied for fixed ratios of waler 10 diesel oil and surfactant to alcohol. In the mixed surfactants (sodium oleate + cctyltrimcthylammonium bromide) ldicscl oill a1cohol/watcr systems, microcmulsion and birefringent phases are formed by adjusting the surfactant ratio E and the cationic weight fraction O. The bicontinuous-ebircfringcnt-e-o/w microcmulsion transition takcs place with dilution for i-pentanol-containing systems, The birefringent region shrinks rapidly with increasing alcohol and/or CTAB weight fractions in total surfactant concentration. The normal solunon-sw/o microemulsion transition for n-hexanol systems and only wlo microemulsion for n-octanol systems were observed along the dilution with diesel oil and water. And microemulsiou domain enlarges with increasing E for three alcohol systems. The optimum surfactant concentration y increases and the corresponding optimum /) decreases with increasing E and the optimum y decreases with increasing the alcohol chain length from i-pentanol to n-octanol and the optimum () decreases in the order of i-pentanol > n-octanol > n-hexanol. Conductivity

“…ethyl or n-propyl groups, have been used in flotation processes (23] and have offered a direct means of investigating the influence of a low degree of hydrophobic shielding of the polar part in a microemulsion. The cationic surfactants have recently [24] been shown to give remarkably high solubilization of water in w/o microemulsions at high oil content.…”

mentioning

confidence: 99%

Effect of Shielding of Head Group of Surfactant on the Microemulsion Region of the Systems Water/Decane/Pentanol/Hexadecyltrialkylammonium Bromides

Friberg

Hakala

Downey

1986

Microemulsion areas were determined for the combination water/decane/pentanol with a series of surfactants. hexadecyltrialkylammonium bormides, in which the alkyl groups were methyl.ethyl and propyl.The enhanced hydrophobic shielding of the surfactant polar group led to enhanced solubility of the surfactant in the alcohol and alcohol/hydrocarbon mixtures and a concordant transfer of the w/o solubility area towards higher surfactant/cosurfactant ratios.