We prepd. stable oil-in-water emulsions of argan oil with two different types of mixts. of nonionic emulsifiers. Three different types of oil (Israeli argon oil, Moroccan argan oil, and soybean oil) were emulsified with mixts. of Span 80 and Tween 80. The optimum HLB value for argan oil was 11.0 (±1.0). The argan oil-in-water emulsions were stable for more than 5 mo at 25°C. Synergistic effects were found in enhancing stability of emulsions prepd. with sucrose monostearate. The origin of the oil and the internal content of natural emulsifiers, such as monoglycerides and phospholipids, have a profound influence on its interfacial properties and on the stability of the argan oil-in-water emulsions. [on SciFinder(R)]

Coating compns. comprise natural or synthetic jojoba oil which is optionally partially or completely hydrogenated and/or isomerized, a solvent, or a dispersing system (an immiscible org. liq. and dispersing agent). The coating compns. are for polymers or plastics or naturally occurring macromols. with high hydrophobicity or with low or medium surface energy. Thus, a coating contained GKF 8-10 (octane-decane) 46.5%, pentane-hexane 46.5%, jojoba oil 5.8%, glycerol 0.5, and fragrances 0.7%. [on SciFinder(R)]

The authors studied the nonionic system water/dodecane/butanol/ polyoxyethylene (10) oleyl alc., and water/dodecane/pentanol/ polyoxyethylene (8) lauryl alc. A pronounced increase in cond. may be the result of a microstructural change, not an inversion from W/O to O/W. Microstructural evolutions of two model systems along two different diln. lines, where the wt. ratios of surfactant/alc./oil are 2:1:1 and 4:3:3, resp., are similar. The inversion from W/O to O/W microemulsion should occur at a water content much higher than 20-30 wt%. (c) 1998 Academic Press. [on SciFinder(R)]

The authors have shown how triangles and tetrahedra can be used to represent the compn. and phase behavior of three- and four-component systems. The relationship between such triangular representations and the full tetrahedron is explained by geometric considerations of the cross-sections through the tetrahedron. [on SciFinder(R)]

The ESR spectra of 1-palmitoyl-2-stearoyl-(n-doxyl)-glycero-3-phosphocholine spin label positional isomers (n = 5, 7, 10, 12 and 16) were studied in soy bean phosphatidylcholine (SPC)-based microemulsions with various vol. fractions of disperse phase over the wide temp. range. The max. hyperfine splitting 2Amax and the order parameters S were taken as indexes of the rotational mobility and the motion spatial restrictions of the labeled lipid chain segments. The temps. Ttr at which sharp enhancements of 2Amax and S occur depend on concn. and size of the reversed micelles in solns. To explain this, a plausible model, taking into account capability of the SPC mol. hydrocarbon chains to change a tilt angle with respect to the surface of a polar head group as temp. varies, is proposed. The estns. of the correlation times $\tau$sl obtained from the lineshape characteristics of the ESR spectra provided the possibility to suggest that these correlation times characterize the reorientations of the SPC chain axis about the normal to the surface of a polar head group of a reversed micelle. [on SciFinder(R)]

A review, with 38 refs. Double emulsions are emulsion-within-emulsion systems with promising applications. Attempts were made to find new amphiphiles to improve their thermodn. stability and to control the release of active matter or markers from double emulsions. The efforts to study the mechanisms of stabilization and release of water-sol. markers from W/O/W double emulsions are summarized, and the achievements in designing an ultimate synthetic graft-comb copolymeric amphiphile for the internal water-oil interface (the W/O emulsion) as well as for the external oil-water interface (the O/W emulsion) are presented. The amphiphilic polymers allow formation of small multicompartment emulsion droplets of W/O/W that are shear (homogenization) and mech. (centrifugation) resistant. The interface is covered with thick emulsifier layers that impart long-term stability. Addn. of controlled amts. of monomeric emulsifiers (Spans) will form reverse micelles in the oil phase, which are capable of transporting the markers via a diffusion-controlled mechanism from the inner to the outer interface. The tailor-made polymers are an excellent soln. to the 2 key problems that, so far, have prevented the use of double emulsions in certain industrial applications: stability and release. Agricultural formulations, based on stabilization by these polymers, have shown considerable advantages over other common techniques of encapsulating or entrapping active matter. [on SciFinder(R)]