Surfactant advantages

Flow injection analysis—mass and tandem mass spectrometry in the analysis of surfactants—advantages and disadvantages 123 Horst Fr. Schroder... 

SPECTROMETRY—II. FLOW INJECTION ANALYSIS—MASS AND TANDEM MASS SPECTROMETRY IN THE ANALYSIS OF SURFACTANTS—ADVANTAGES AND DISADVANTAGES... 

DSO via molybdate-catalyzed disproportionation of HjOj provides a readily scalable alternative to photooxidation. It can be carried out in commonly available stirred-tank reactors. However, the reaction does not work at low temperatures and organic media are limitedto alcoholic polar solvents (methanol or the safer ethylene glycol) or to microstructured media such as one-, two-, or three-phase microemulsion systems. The latter based on balanced catalytic surfactants advantageously combine low surfactant concentration with easy product isolation and catalyst recycling via simple phase separation. Safe processing may be further enhanced by microreactors, which minimize peroxide hold-up. 

Compared to chemical surfactants, advantages of using surfactin containing cleaning remedy are eco-friendliness, better cleaning, cost-effectiveness, and less time dura-tion. " Apart from bioremediation, surfactin in the form of sodium surfactin is also used in cosmetic preparation such as creams, lotions, and face masks. 

Quick-breaking foams consist of a miscible solvent system such ethanol (qv) [64-17-5] and water, and a surfactant that is soluble in one of the solvents but not in both. These foams are advantageous for topical appHcation of pharmaceuticals because, once the foam hits the affected area, the foam coUapses, deUvering the product to the wound without further injury from mechanical dispersion. This method is especially usehil for treatment of bums. Some personal products such as nail poHsh remover and after-shave lotion have also been formulated as quick-breaking foams. 

Emulsions of fatty- and petroleum-based substances, both oils and waxes, of the o/w type are made by using blends of sorbitan fatty esters and their poly(oxyethylene) derivatives. Mixtures of poly(oxyethylene(20)) sorbitan monostearate (Polysorbate 60) and sorbitan monostearate are typical examples of blends used for lotions and creams. Both sorbitan fatty acid esters and their poly(oxyethylene) derivatives are particularly advantageous in cosmetic uses because of their very low skin irritant properties. Sorbitan fatty ester emulsifiers for w/o emulsions of mineral oil are used in hair preparations of both the lotion and cream type. Poly(oxyethylene(20)) sorbitan monolaurate is useflil in shampoo formulations (see Hairpreparations). Poly(oxyethylene) sorbitan surfactants are also used for solubilization of essential oils in the preparation of colognes and after-shave lotions. 

A reexamination of so-called renewabdity has shown that advantages for oleochemicals are not sufftcientiy clear (115), especially because manufacture of surfactants ia the United States accounts for only 0.03% of aimual cmde oil consumption (62). On these bases, the primary determinants of surfactant choice will continue to be cost effectiveness and availability. The 1993 U.S. market has been estimated to be worth 3.7 x 10 (110). Approximately one-half was anionic surfactant ( 1.8 x 10 ) and one-third nonionic surfactant ( 1.2 x 10 ). The balance was made up by cationics ( 1.2 X 10 ) and amphoterics ( 600 x 10 ). The U.S. International Trade Commission (116) provides a minutely detailed breakdown of surfactant production. 

Very good water and moisture resistance. Solvent-borne adhesives have an advantage over latex, which contains surfactants. 

The other type of porous glass that has cylindrical pores is mesoporous silicate (MPS) (14,15). The advantage of MPS is in its feasibility to make a small pore diameter, typically below 10 nm. A columnar-phase liquid crystal, formed from surfactant molecules with a long alkyl chain tail and silicate molecules, is calcined to remove hydrocarbons. At the end, a hexagonal array of straight and uniform cylindrical holes is created in a crystalline order. MPS is not available commercially either. 

Functionalized polyelectrolytes are promising candidates for photoinduced ET reaction systems. In recent years, much attention has been focused on modifying the photophysical and photochemical processes by use of polyelectrolyte systems, because dramatic effects are often brought about by the interfacial electrostatic potential and/or the existence of microphase structures in such systems [10, 11], A characteristic feature of polymers as reaction media, in general, lies in the potential that they make a wider variety of molecular designs possible than the conventional organized molecular assemblies such as surfactant micelles and vesicles. From a practical point of view, polymer systems have a potential advantage in that polymers per se can form film and may be assembled into a variety of devices and systems with ease. 

As detergent manufacturers responded to consumer trends the number of mixed active detergent products increased. The combination of LAS with other surfactants in mixed active systems can provide several advantages over a single active LAS system. These advantages can include the following ... 

The introduction of concentrated laundry detergent powders in Japan during 1986-1987 produced a substantial increase in the consumption of LAB in the subsequent 3-4 years as the market changed from low-density, spray-dried powders to the concentrated (compact) products. In these products, which may contain up to 40% surfactant, the cost/performance advantages of LAS are of significance. In addition, LAB sulfonic acid is well suited for the production of high-active, high-density (about 1.0 g/cm3) laundry powders by routes other... 

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