Emulsifying power

It was found that if less soap were employed the emulsions were unstable. The experimental results agree with the conclusion that the soaps exert their emulsifying powers on oil-water mixtures by going to the interface and coating the interface with a layer of soap one molecule deep. 

Marie P, Herrenschmidt YL, Gallot Y. Study of the emulsifying power of the block copolymers polystyrene/poly(2-vinylpyridinium chloride) and polyisoprene/poly(2-vinylpyridinium chloride). Makromol Chem 1976 77 2773-2780. 

These emulsions are liquid-liquid systems comprising immiscible polymer solutions in nonpolar solvents and BG copolymer emulsifiers. The emulsifying power of BG copolymers has been attributed (12) to coalescence barriers formed by accumulation of the BG copolymers in the emulsion interface. This interface apparently has the structure of a double layer consisting of the different subchains of the BG copolymers which are solvated by the organic solvent. The chemically different sequences in BG copolymers are separated in different layers in the interface because polymer chains of different chemical structures are usually incompatible (3, 4), particularly in nonpolar solvents. 

Ten aspects of the Maillard reaction will be considered in this chapter the effect on a,, on pH, on redox potential, on solubility, on texture, on foamability and foam stability, on emulsifying power, on volatile formation on storage, on binding of volatiles, and on other functionalities. The third of these has received by far the most attention and this is reflected here. 

The emulsion stability of gum arabic (at constant nitrogen content) was found to increase with the polysaccharide molecular weight (Dickinson et al., 1991a, b). The emulsifying power is attributed to preferential adsorption of the protein moiety that bonds hydrophobically with oil, leaving the hydrophilic polysaccharide moiety free to protrude from the droplet surface into the surrounding aqueous medium (Randall et al., 1988). 

Phosphate esters are widely used in metalworking and lubricants. A C12 h with 6 mol of ethylene oxide (diester) can be used as an emulsifier but also as an extreme pressure additive - it can reduce wear where there is high pressure metal to metal contact. PEs can also show corrosion inhibiting properties, as with petroleum sulphonates and the emulsifying power of PEs with low foam is used in agrochemical formulations. PEs can act as dispersants or hydrotropes in plant protection formulations, allowing the development of easy-to-handle and dilute formulations of both poorly miscible and insoluble herbicides. 

When the polarity of the end group of the peptidic chain decreases, the emulsifying power of the lipopeptide decreases. 

Monawets [ICI]. TM for a group of surfactants of di-octyl, di-hexyl, di-isobutyl, and di-tride-cyl sulfosuccinates known for their wetting, spreading, penetrating and emulsifying power. 

Emulsions are usually formed, for instance, due to over-agitation, interfacial tension, low-density difference, or the inherent nature of the compounds involved. In our case the extraction problems were supposed to stem from the high density of both substrate and product (<5 > 1) combined with their high concentrations in the reaction mixture, the emulsifying power of the enzyme, and loose solid fines that floated at the interface. In some very highly concentrated experiments (cf. Section 5.4.2) the organic phase had an even higher density than the aqueous phase. 

Correlations between the chemical structure of surface-active agents and their emulsifying power are complicated by the fact that both phases, oil and water, are of variable composition. This is in contrast to such phenomena as foaming or wetting, where one phase (the air) is more or less constant and some specific correlations can be made between structure and activity. Moreover, the concentration at which the emulsifying agent is used determines not only its emulsifying power, but even the type of emulsion (O/W or W/O) formed. As a result of this... 

For a POE surfactant with a given HLB value, as the polarity of the oil phase decreases, the PIT increases. (The surfactant must be made more lipophilic to match the decreased polarity of the oil.) Thus, to keep the PIT constant (and hence a constant emulsifying power balance), the surfactant used must have a lower HLB value as the polarity of the oil phase decreases. The PIT of an emulsion made from binary mixture of oils is the weighted average, by volume, of the PITs of the emulsion made from the individual oils, using the same emulsifying agent (Arai, 1967) ... 

Note Use Britesil H20 in place of Metso Beads 2048, partially or fully, if lower alkalinity is desired and more suspending/ emulsifying power is needed. Britesil H20 will also increase the surfactant adsorbency of detergent blend. 

Emulsifying power is an important consideration in the evaluation of tragacanth. For this purpose Turkish flakes are often preferred over the Persian. Turkish flakes make heavier and thicker solutions which are less white and less attractive in appearance than the Persian, but because of the heavier consistency and because it contains less starch than Persian the Turkish gum is a better emulsifier. In fact. No. 4 Turkish flakes have fair emulsifying qualities, whereas No. 4 Persian flakes would be of little value for this purpose. 

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