Surfactants as emulsifiers

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... 

A microemulsion fuel suitable for use in diesel engines has been prepared from diesel fuel, ethanol, traces of water and cationic surfactants as emulsifiers, plus other additives [94]. Suitable cationic surfactants are alkyl polyamines and their alkoxylates. The fuels benefit from improved lubricity. 

No systematic studies of the use of silicone surfactants as emulsifiers have yet been published. Silicone polyoxyalkylene copolymers with relatively high molecular weight and a high proportion of silicone are effective water-in-silicone oil emulsifiers and a recent study of these copolymers suggests that they stabilize emulsions by a solid-particle mechanism [68]. This type of silicone surfactant has been used to prepare transparent water-in-oil emulsions (often with an active ingredient in the internal phase) for use as deodorants or antiperspirants as well as cosmetics and other personal care products. Their use as drug delivery vehicles has also been claimed. These copolymers can also be used to prepare multiple emulsions not requiring a two-pot process. 

USE Pharmaceutic aid (surfactant) as emulsifier and dispersing agent in medicinal products as defoamer and emulsifier in foods. 

A mixture of 30 cm oil and 70 cm water is emulsified using a polymeric surfactant as emulsifier/stabilizer. The result is an pulsion representing 30m interfacial area. The interfacial tension of the monolayer at the oil/water interface is 20 mN m". The emulsification occurs in an insulated container in which the temperature rises from 20°C to 65°C. Calculate the total interfacial Gibbs... 

Today, SBR elastomers are widely manufactured with only minor improvements in the GR-S recipe. One such is the use of synthetic surfactants as emulsifiers. These and other improvements allow the production of more uniform latex particles. 

This subject has attracted special attention in recent years [18]. As mentioned above, the use of polymeric surfactants as emulsifiers and dispersants is desirable... 

The use of surfactants as emulsifying agents, solubilizers, dispersants for suspensions and as wetting agents in the formulation can lead to significant changes in the biological activity of the dmg in the formulation. Surfactant molecules incorpo-... 

Microemulsions, consisting of water-in oil (dodecane plus hexa-nol) stable and optically clear dispersions with an ionic surfactant as emulsifier, demonstrate several peculiar properties depending on the amount of water present (1 3). 

Nuyken, O. Meindl, K. Wokaun, A. Mezger, T. A light-sensitive diazosulfonate surfactant as emulsifier for emulsion polymerization. Macro-mol. Rep. 1995, A32, 447 57. 

The generalizations of Eqs. (26) and (27) to the case of surfactant soluble in two adjacent liquid phases have been obtained by Miller [71]. It was demonstrated that the distribution coefficient, K, [see Eq. (22)] can be determined from experimental data for the dynamic interfacial tension. Because this coefficient is closely related to the hypophilic-lipophilic balance (HLB) value [72], such experiments would be useful to characterize the application of surfactants as emulsifiers. 

The fundamental difficulty with the emulsification of fluorochemical oxygen carriers in water is the interface between the fluorochemical and water. The use of ordinary surfactants as emulsifiers results in a fluorophilic-lipophilic interface between the droplet and the surfactant and, consequently, in a high interfacial tension. The stability of emulsions prepared with lipophilic-hydrophilic-type surfactants is therefore only marginal. Therefore, emulsifier systems consisting of two components have been proposed [102-106,130]. 

Surfactants as emulsifiers ensure the stability of emulsions. They behave like polar substances which reduce the interfacial tension between the immiscible liquids. Their mode of action can be schematically illustrated as follows [39] ... 

Interesting opportunities of morphology regulation of oligomeric systems offers usage of surfactants as emulsifiers. The experience, accumulated at investigation of latex and other... 

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