Solubilization soft surfactant systems

Hild to the skin. Compatible with anionic, cationic and nonionic surfactants. Excellent viscosity builder and gelling agent. Hard-water tolerance permits equally good foaming in hard and soft water. Stable in high-electrolyte solutions and will help solubilize other surfactants into these systems. Stable in acidic and alkaline conditions, functioning as cationic in acid media and as anionic in alkaline. Lime soap dispersant. 

It is generally accepted that the soft-core RMs contain amounts of water equal to or less than hydration of water of the polar part of the surfactant molecules, whereas in microemulsions the water properties are close to those of the bulk water (Fendler, 1984). At relatively small water to surfactant ratios (Wo < 5), all water molecules are tightly bound to the surfactant headgroups at the soft-core reverse micelles. These water molecules have high viscosities, low mobilities, polarities which are similar to hydrocarbons, and altered pHs. The solubilization properties of these two systems should clearly be different (El Seoud, 1984). The advantage of the RMs is their thermodynamic stability and the very small scale of the microstructure 1 to 20 nm. The radii of the emulsion droplets are typically 100 nm (Fendler, 1984 El Seoud, 1984). 

Poly(propylene oxide) is typically obtained by base catalyzed anionic polymerization of propylene oxide [12]. Both stereospecific and atactic forms are known. The polymer is used as a soft polyether unit in polyurethane elastomers and foams in polymer electrolytes as surfactants (lubricants, dispersants, antistatic agents, foam control agents) in printing inks, as solubilizers in hydraulic fluids, coolant compositions in various medical applications (protective bandages, drug delivery systems, organ preservation, dental compositions), etc. 

Garti, N., Spernath, A., Aserin, A. and Lutz, R. (2005) Nano-sized self-assemblies of nonionic surfactants as solubilization reservoirs and microreactors for food systems. Soft Matter, 1(3), 206-218. 

A well-studied model system for the case of soft charged interfaces is that of the AOT surfactant, having two branched short chains, in the presence of oil and water. Solubilization in water-in-oil microemulsions has been studied by Zemb and co-workers (45) in the case of the water-oil-AOT system. The topology of these microemulsions is dominated by geometrical constraints as the interfacial area, cr = 0.6 nm /molecule, of the surfactant is invariant with composition within experimental uncertainty. If partial molar volume of water variations are neglected, the radius of the droplets is imposed by the composition of the microemulsions. 

Uses Emollient, lubricant, solubilizer, emulsifier, plasticizer for cosmetics, pharmaceuticals, sun preps. emollient and surfactant in aq. and hydtoalcoholic systems conditioner for shampoos superfatting agent for hand soaps and waleriess cleaners imparts soft, nonsticl f%l in creams and ointments Properties Yel. flakes, char, odor water sol. m.p. 45 C min. acid no. 2 max. ... 

Uses Surfactant for oral SE drug delivery systems bioavailability enhancer, emulsifier, solvent, solubilizer for pharmaceutical orals, topicals, vaginals, rectals, and nasals, soft or hard gelatin capsules... 

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