Emulsion salt stability

Dickinson, E., Semenova, M.G., Antipova, A.S. (1998b). Salt stability of casein emulsions. Food Hydrocolloids, 12, 227-235. 

Casanova, H., Dickinson, E. (1998). Influence of protein interfacial composition on salt stability of mixed casein emulsions. Journal of Agricultural and Food Chemistry, 46, 72-76. 

For ionic surfactants another effect often dominates and usually salt tends to stabilize emulsions. Reason without salt the distance between surfactants in the interface is large because the molecules electrostatically repel each other. This prevents a high surface excess. The addition of salt reduces this lateral repulsion and more surfactant molecules can adsorb at the interface. Then, according to the Gibbs adsorption isotherm Eq. (3.52), the surface tension is reduced and the emulsion is stabilized. 

The emulsion polymerization of styrene with shellac salt stabilizer yields a highly crosslinked, F/T stable emulsion from which it is not possible to extract all the shellac by conventional means (21). This may be interpreted in a similar manner although it has not, as yet, been possible to determine the sites on the shellac which undergo chain transfer. 

Mayonnaise (Figure 2.21) is an OAV emulsion consisting of 50 to 85% edible oil, 5 to 10% egg yolk, vinegar, salt, and seasonings. The emulsion is stabilized by egg yolk phospholipids. Tung and Jones (1981) studied the mayonnaise microstructure by conventional SEM and observed a high concentration of dispersed phase... 

Uses Coemulsifier for poiyacryiates, acrylate vinyl acetate copolymers costabilizer to inc. mech. or salt stability of polymer disps. dispersant for emulsion paints food pkg. adhesives, paper/paperboard emulsifier in mfg. of food-contact articles... 

Uses Dispersant, wetting agent, emulsifier for pojymerization, emulsion paints, brush cleaners, wallp er removers, pigment preps., binder emulsions surfactant costabilizer to inc. mech. or salt stability of polymer disps. emulsifier for mfg. of o/w emulsions food pkg. adhesives, paper/paperboard emulsifier in mfg. of food-contact articles Regulatory FDA 21CFR 175.105,176.180,178.3400 BGA approved Properties Clear liq. dens. 1.022-1.026 g/cm (70 C) FILB 13.4 hyd. no. 84-91 set pt. 7 C doud pt. 60-65 C (1 g/99 cm water) nonionic 99% min. act. <0.5% water... 

Uses Surfactant solubilizer, detergent for household/industrial detergents, cosmetics, textiles, leather, agric., paints/coatings, emulsion polymerization, iubricants, silicon and wax emulsions, metal treatment, paper processing costabilizer to increase mechanical or salt stability in polymer dispersions... 

FIGURE 11.1. There are four primary mechanisms for the stabilization of emulsions (plus combinations, of course). Some emulsions may be weakly stabilized by the presence of adsorbed ions and nonsurface-active salts (a). The presence of colloidal sols partially wetted by both phases of the emulsion may form a mechanical barrier to drop contact and coalescence (b). Many emulsions are stabilized by adsorbed polymer molecules (c). Along with polymers, adsorbed surfactant molecules represent the most common stabilization mechanism (d). 

Salt derivatives for emulsion polymerizations Salt stabilizers for emulsion polymerizations Synthetic resin dispersant agent... 

Uses Costablllzer to Inc. mechanical or salt stability In polymer dispersions used as emulsifier In mfg. of o/w emulsions Regulatory FDA and BGA approved Properties LIq. HLB 8.1 > 99% act. 

Uses Emulsifier for emulsion polymerization, o/w emulsions costabilizer to inc. mech. and salt stability of polymer disps. solubilizer dispersant latex stabilizer food-contact paper/paperboard Regulatory FDA 21CFR 176.180 Properties Flakes HLB 16.5 100% act. 

Aqueous emulsion polymerization is carried out using a fluorinated emulsifier, a chain-transfer agent to control molecular weight, and dispersion stabilizers such as manganic acid salts and ammonium oxalate (13,14). 

The product of an emulsion polymerization is a latex ie, polymer particles on the order of 0.5—0.15 p.m stabilized by the soap. These form the basis for the popular latex paints. SoHd mbber is recovered by coagulating the latex with ionic salts and acids (see Latex technology). 

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