Surfactant emulsifier synthetic

A large volume and variety of chemicals are used in oil- and gas-field activities for drilling, completion and production. These chemicals are inorganic (bentonite, other clays, BaS04, salts), petrochemicals (surfactants, emulsifiers, synthetic polymers, mineral oils) and products based on RR. The following discussions are limited to the latter. 

The range of surfactant emulsifiers used in pharmaceutical preparations is illustrated in Table 2. Surfactants are manufactured from a variety of natural and synthetic sources and consequently they show considerable batch-to-batch variations in their homologue compositions and in trace impurities from the starting material. For example, batch variations in the number of neutral phospholipids occur in lecithin surfactants and non-ionic polyethylene surfactants show variations in the number of moles of ethylene oxide. The mechanisms by which such batch variations lead to differences in emulsifying properties are now better understood. Although synthetic and semisynthetic surfactants form by far the largest group of emulsifiers studied in the scientific literature and many of them are available commercially, their use in pharmaceutical emulsions is limited by the fact that the majority are toxic (i.e., haemolytic) and irritant to the skin and mucous... 

Latex-based polymer materials can be either nature-made, as natural rubber [Stern, 1967 White, 1995], or synthetically made. The synthetically made latexes are commonly based on recipes of monomer, water, surfactant, and free radical initiator to induce chain polymerization [Lovell and El-Aasser, 1997 Wickson, 1993], However, recipes based on step polymerization are also well known, often resulting in crossUnked films [Walker and Shaffer, 1996], The resulting latex material consists of small particles, usually spherical, of 50-500 nm in diameter, dispersed in water. Alternately, polymers are sometimes emulsified after polymerization (direct emulsification, the product sometimes called artificial latexes) via agitation of a melt in the presence of water and surfactant (emulsifier), and sometimes organic solvent or plasticizer [Piirma, 1989]. 

OTHER COMMENTS used as a solvent for casein, albumin, shellac, and sulfur used in the manufacture of surfactants, emulsifying agents, wetting agents, dispersants, corrosion inhibitors, detergents, and textile surface treatments used in preparation of dyes, synthetic waxes, resins, insecticides, and asphalt wetting agents also used as an inhibitor in antifreeze solutions has been used as a pharmaceutical aid. 

Emulsion polymerization is among the most popular synthetic routes to prepare vinyl-based pH-responsive polymers, especially microgel systems (Rao and Geckeler, 2011). This technique employs a radical chain polymerization methodology to form latexes of narrow particle size distributions. The emulsion polymerization systems are commonly composed of monomer(s), water, water-soluble initiator and surfactant (emulsifier). Colloidal stabilizers may be electrostatic, steric or electrosteric, or display both stabilizing mechanisms. When phase separation occurs, the formation of solid particles takes place before or after the termination of the polymerization reaction. 

Acrylic latexes are high MW acrylic (co)polymer particles dispersed in water. Synthetic latexes are prepared by a radical polymerization mechanism using an emulsion polymerization technique. The emulsion polymerization is carried out in water using monomer(s), surfactant (emulsifier) and water-soluble initiator. In a typical manufacturing process, an initiator and a separate emulsion of monomer(s) in water are slowly added to a reaction vessel containing water and emulsifier, at a predetermined rate. Polymerization of monomers occurs within tiny pockets formed by aggregation of emulsifier molecules, called micelles, resulting in formation... 

Uses Surfactant, emulsifier, wetting agent, dispersant, synthetic iatex stabiiizer, and detergent in formuiating cieaning prods. 

Uses Surfactant emulsifier for emulsion polymerization of synthetic rubber and resin... 

Early efforts to produce synthetic mbber coupled bulk polymerization with subsequent emulsification (9). Problems controlling the heat generated during bulk polymerization led to the first attempts at emulsion polymerization. In emulsion polymerization hydrophobic monomers are added to water, emulsified by a surfactant into small particles, and polymerized using a water-soluble initiator. The result is a coUoidal suspension of fine particles,... 

The most commonly used emulsifiers are sodium, potassium, or ammonium salts of oleic acid, stearic acid, or rosin acids, or disproportionate rosin acids, either singly or in mixture. An aLkylsulfate or aLkylarenesulfonate can also be used or be present as a stabilizer. A useful stabilizer of this class is the condensation product of formaldehyde with the sodium salt of P-naphthalenesulfonic acid. AH these primary emulsifiers and stabilizers are anionic and on adsorption they confer a negative charge to the polymer particles. Latices stabilized with cationic or nonionic surfactants have been developed for special apphcations. Despite the high concentration of emulsifiers in most synthetic latices, only a small proportion is present in the aqueous phase nearly all of it is adsorbed on the polymer particles. 

Petroleum sulfonates are widely used as solubilizers, dispersants (qv), emulsifiers, and corrosion inhibitors (see Corrosion and corrosion inhibitors). More recentiy, they have emerged as the principal surfactant associated with expanding operations in enhanced oil recovery (66). Alkaline-earth salts of petroleum sulfonates are used in large volumes as additives in lubricating fluids for sludge dispersion, detergency, corrosion inhibition, and micellar solubilization of water. The chemistry and properties of petroleum sulfonates have been described (67,68). Principal U.S. manufacturers include Exxon and Shell, which produce natural petroleum sulfonates, and Pilot, which produces synthetics. 

Poly(vinyl acetate) emulsions can be made with a surfactant alone or with a protective coUoid alone, but the usual practice is to use a combination of the two. Normally, up to 3 wt % stabilizers may be included in the recipe, but when water sensitivity or tack of the wet film is desired, as in some adhesives, more may be included. The most commonly used surfactants are the anionic sulfates and sulfonates, but cationic emulsifiers and nonionics are also suitable. Indeed, some emulsion compounding formulas require the use of cationic or nonionic surfactants for stable formulations. The most commonly used protective coUoids are poly(vinyl alcohol) and hydroxyethyl cellulose, but there are many others, natural and synthetic, which are usable if not preferable for a given appHcation. 

Emulsion polymerisation represents the next stage in development from the suspension technique and is a versatile and widely used method of polymerisation. In this technique droplets of monomer are dispersed in water with the aid of an emulsifying agent, usually a synthetic detergent. The detergent forms small micelles 10-100 /im in size, which is much smaller than the droplets that can be formed by mechanical agitation in suspension polymerisation. These micelles contain a small quantity of monomer, the rest of the monomer being suspended in the water without the aid of any surfactant. 

Synthetic surfactants are commonly used in shampoos, sometimes for reasons of cost and sometimes for performance. Non-ideal mixing in micelles can result when the repulsions between different surfactant head-groups are not uniform, such as when an anionic sulfonate is mixed with a non-ionic ethoxylate or when an anionic is mixed with a betaine. This causes the cmc of the mixture to be smaller than would be the case for ideal mixing, or for either surfactant alone. Such a reduction in cmc can be used to reduce the surfactant monomer concentration in a shampoo. This is an advantage since reducing the monomer concentration reduces the amount of eye and skin irritation experienced when the shampoo is used [904], Other synthetics offer other benefits. For example, some silicone surfactants can not only function as emulsifiers in hair and skin care products, but also act to improve feel, gloss, sheen, emolliency, conditioning and foam stabilization [905]. 

The use of surfactants in the food industry has been known for centuries. Naturally occurring surfactants such as lecithin from egg yolk or soybean and various proteins from milk are used for the preparation of many food products, such as mayonnaise, salad creams, dressing, and desserts. Polar lipids such as monoglycerides have been introduced as emulsifiers for food products. More recently, synthetic surfactants such as sorbitan esters (Spans) and their ethoxylates (Tweens), sucrose esters, have been used in food emulsions. It should be mentioned that the structures of many food emulsions is complex, and in... 

In personal care, washing involving the body, hair and teeth is the fundamental application of surfactants and there are also important roles played by surfactants as emulsifiers in skin care products. In the late 1970s the hand soap market was revolutionised by the introduction of liquid soaps based on synthetic surfactants as opposed to the bar soaps based on natural... 

This material is the sodium salt of an alkaline alkylaryl suphonate. This synthetic detergent and surfactant serves as an emulsifier, detergent, exhibiting some wetting efficiency and rewetting properties. Supplied at 35% and 25% concentrations. ... 

Is a water-soluble surfactant used as a base lubricant for synthetic fiber spin finishes, open end spinning, and overspray finishes. It is also an excellent co-emulsifier and coupling agent for many formulations. 

As mentioned previously, soybean lecithin is used in food because of its emulsifying, wetting, release, and other surfactant qualities. Relatively small amounts of the lecithin are needed, often only 0.1% to 2% in foods. These use levels are more or less consistent with those of chemical surfactants (7). At these low levels of usage, the color, flavor, and odor of the lecithin normally are not noticeable. When lecithin is used in conjunction with synthetic emulsifiers, it sometimes has a synergistic effect, and thus lesser amounts of the synthetic emulsifiers need be used. 

The techniques used in the preparation of a stable oil-in-water emulsion for pipeline transportation are illustrated by the results of a field test in which an Athabasca bitumen was emulsified and pumped through a 3-in. x 4000-ft. pipe-loop system for a total distance of approximately 500 miles. The emulsion in this case comprised 75% by weight of the 8.3 API bitumen and 25% of a synthetic brine containing 1.7% NaCl. (API gravity is defined in the Glossary.) The surfactant used was a mixture of two ethoxylated nonylphenol surfactants the first component contained an average of 40 ethylene oxide units per molecule, and the second component contained 100 units. Approximately 1500 ppm of the surfactant mixture, based on the total... 

Nonionic surfactants are one of the most important and largest surfactant groups. They are amphiphilic molecules composed, in most cases, of poly(ethylene oxide) (PEO) blocks as the water-soluble fragment and fatty alcohols, fatty acids, alkylated phenol derivatives, or various synthetic polymers as the hydrophobic part [1], This class of surfactants is widely used as surface wetting agents, emulsifiers, detergents, phase-transfer agents, and solubilizers for diverse industrial and biomedical applications [2],... 

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