Agents natural emulsifying

Chemical nature Emulsified defoamlng agent Appearance Fluid white emulsion pH 5% solution 7.2 at 25C. 

Phospholipids are well-known natural emulsifiers, wetting and dispersing agents, as well as liposome formers. They already have many food and pharmaceutical... 

Surface-active agent. (surfactant). Any compound that reduces surface tension when dissolved in water or water solutions, or that reduces interfacial tension between two liquids, or between a liquid and a solid. There are three categories of surface-active agents detergents, wetting agents, and emulsifiers all use the same basic chemical mechanism and differ chiefly in the nature of the surfaces involved. 

The sodium salt of this acid is a normal constituent of bile. Thus, it is a natural emulsifying agent aiding in the digestion of fats. It is a GRAS (generally recognized as safe) food additive employed as an emulsifier. 

As a natural emulsifier Quillaya and Yucca saponins have been used in the following ways for products patented in Japan (Natural foaming agents quillaya and yucca, DK Int. commercial leaflet) ... 

Chem. Descrip. Linear sat. fatty alcohol polyglycol ether Ionic Nature Nonionic Chem. Analysis 0.5 max. moisture Uses Wetting agent, polymerization emulsifier, dispersant Properties Solid dens. 0.908-0.911 g/cm solid.pt. 31-35 C HLB 9.2 hyd. no. 114-122 cloud pt. 53-63 C pH 6.0-7.5 99-100% act. 

Chem. Descrip. Polyglycol ether, modified Ionic Nature Anionic/nonionic Uses Scouring agent and emulsifier for min. oils Properties Liq., solid. 

Ionic Nature Nonionic Chem. Analysis < 0.5% nnoislure Uses Wetting agent detergent emulsifier Features Low foaming... 

Chem. Descrip. PEG 200 Ionic Nature Nonionic Chem. Analysis < 0.5% moisture CAS 25322-68-3 EINECS/ELINCS 203-989-9 Uses Wetting agent dispersant emulsifier softener in paper finishing Properties APHA < 40 liq. m.w. 200 sp.gr. 1.120 hyd. no. 562 pH 6.0 Sinopol PEG300 [Sino-Japan]... 

Chem. Descrip. Modified natural oils Uses Fluid loss agent, primary emulsifier for Invert muds Features Must be activated with lime eliminates sm. levels of water Properties Orange vise. Ilq. disp. In oil Insol. In water sp.gr. 0.96-0.97 pour pt. 32 F flash pt. > 158 F UseLevei 05-2,0Ib/bbI Wellguard 1899 [Albemarle]... 

Chem. Descrip. Sodium-N-coco beta-aminoprepionate Ionic Nature Amphoteric EINECS/ELINCS 271-795-1 Uses Wetting agent and emulsifier... 

Uses Foaming agent, stabilizer, emulsifier, foam additive for natural and syn, latexes emulsion polymerization wetting agent for latex impregnation Properties Soft creamy paste or Iiq. pH 9-10 (10% solids) 35% solids Rewomid 203/S [Evonik Goldschmidt]... 

Crude oil containing brine generally results in the formation of stable water-in-oil (W/O) emulsions when turbulent mixing conditions are encountered during the transportation process. The dispersion of water droplets in oil is facilitated by the presence of interfacial active agents in the crude oil such as asphaltenes, waxes, resins and naphthenic acid (Schramm, 1992). The quantity of these natural emulsifiers is more abundant in heavy than in light crude oils and, thus, the formation of more stable emulsions in heavy crude oils (Kokal, 2005). 

One may rationalize emulsion type in terms of interfacial tensions. Bancroft [20] and later Clowes [21] proposed that the interfacial film of emulsion-stabilizing surfactant be regarded as duplex in nature, so that an inner and an outer interfacial tension could be discussed. On this basis, the type of emulsion formed (W/O vs. O/W) should be such that the inner surface is the one of higher surface tension. Thus sodium and other alkali metal soaps tend to stabilize O/W emulsions, and the explanation would be that, being more water- than oil-soluble, the film-water interfacial tension should be lower than the film-oil one. Conversely, with the relatively more oil-soluble metal soaps, the reverse should be true, and they should stabilize W/O emulsions, as in fact they do. An alternative statement, known as Bancroft s rule, is that the external phase will be that in which the emulsifying agent is the more soluble [20]. A related approach is discussed in Section XIV-5. 

Emulsion Adhesives. The most widely used emulsion-based adhesive is that based upon poly(vinyl acetate)—poly(vinyl alcohol) copolymers formed by free-radical polymerization in an emulsion system. Poly(vinyl alcohol) is typically formed by hydrolysis of the poly(vinyl acetate). The properties of the emulsion are derived from the polymer employed in the polymerization as weU as from the system used to emulsify the polymer in water. The emulsion is stabilized by a combination of a surfactant plus a coUoid protection system. The protective coUoids are similar to those used paint (qv) to stabilize latex. For poly(vinyl acetate), the protective coUoids are isolated from natural gums and ceUulosic resins (carboxymethylceUulose or hydroxyethjdceUulose). The hydroHzed polymer may also be used. The physical properties of the poly(vinyl acetate) polymer can be modified by changing the co-monomer used in the polymerization. Any material which is free-radically active and participates in an emulsion polymerization can be employed. Plasticizers (qv), tackifiers, viscosity modifiers, solvents (added to coalesce the emulsion particles), fillers, humectants, and other materials are often added to the adhesive to meet specifications for the intended appHcation. Because the presence of foam in the bond line could decrease performance of the adhesion joint, agents that control the amount of air entrapped in an adhesive bond must be added. Biocides are also necessary many of the materials that are used to stabilize poly(vinyl acetate) emulsions are natural products. Poly(vinyl acetate) adhesives known as "white glue" or "carpenter s glue" are available under a number of different trade names. AppHcations are found mosdy in the area of adhesion to paper and wood (see Vinyl polymers). 

Larch gum is readily soluble in water. The viscosity of these solutions is lower than that of most other natural gums and solutions of over 40% soHds are easily prepared. These highly concentrated solutions are also unusual because of their Newtonian flow properties. Larch gum reduces the surface tension of water solutions and the interfacial tension existing in water and oil mixtures, and thus is an effective emulsifying agent. As a result of these properties, larch gum has been used in foods and can serve as a gum arabic substitute. 

Phospholipids. Phospholipids, components of every cell membrane, are active determinants of membrane permeabiUty. They are sources of energy, components of certain enzyme systems, and involved in Hpid transport in plasma. Because of their polar nature, phosphoUpids can act as emulsifying agents (42). The stmcture of most phosphoUpids resembles that of triglycerides except that one fatty acid radical has been replaced by a radical derived from phosphoric acid and a nitrogen base, eg, choline or serine. 

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