Applications of emulsifiers

Graven, S. Application of Emulsifiers and Stabilisers in Selected Dairy Products. Grindsted Technical Paper 215 (1989). 

Contrary to instillation of standard eyedrops, unilateral application of emulsified pilocarpine induced a biphasic effect in (he contralateral eye, presumably due to systemic absorption. The authors concluded tha(, in spite of (his drawback, (he pilocarpine submicrometer emulsion might serve as a long acting antiglaucoma preparation, requiring a single daily instillation. In another... 

Field Application of Emulsified Acids. Surfactants are used to form emulsified acid, where acid is the dispersed or internal phase. Pumping the acid in this form reduces acid contact with the rock. This enables the acid to form deep wormholes. It also reduces acid contact with the native crude. This will reduce sludge precipitation and associated problems [42]. 

Styrene—butadiene latexes generally are quite stable mechanically because of the presence of relatively large amounts of emulsifying and stabilizing agents, and therefore require addition of less stabilizer in compounding. The apphcations of SBR latex are classified in Table 21. This classification indicates the scope of the industry and illustrates the large number of diverse applications in which synthetic latices are employed. The latex types previously found most suitable for particular applications are also listed. 

MAI composed of PAIE for application to emulsifiers, drug carriers, and ion-exchange resins [60,61]. Poly(per-fluoropropyleneglycol)-b-poly(acrylic acid) was synthesized initiated with an MPI having fluoroalkyl group in the main chain [62]. It was soluble to water, ethanol, and THF, and showed water repellency, oil repellency, antifouling, and resistance to chemicals. 

Finally, to evaluate the membranes, analysis such as X-ray diffraction (XRD), SEM, TEM and light scattering were performed at the School of Mineral and Material Engineering, Universiti Sains Malaysia. The last part of the work, testing the produced membrane to remove emulsifier oil from domestic wastewater, was accomplished on a limited budget. An experimental rig and membrane module were required. Also the need for experimental data for the application of the supported membrane may show the real success of this project. 

The performance of secondary alkanesulfonates in applications as emulsifiers in the widespread emulsion polymerization of vinyl monomers can be assessed by their hydrophilic-lipophilic balance (HLB) numbers. The HLB numbers can... 

Hydrosilation reactions have been one of the earlier techniques utilized in the preparation of siloxane containing block copolymers 22,23). A major application of this method has been in the synthesis of polysiloxane-poly(alkylene oxide) block copolymers 23), which find extensive applications as emulsifiers and stabilizers, especially in the urethane foam formulations 23-43). These types of reactions are conducted between silane (Si H) terminated siloxane oligomers and olefinically terminated poly-(alkylene oxide) oligomers. Consequently the resulting system contains (Si—C) linkages between different segments. Earlier developments in the field have been reviewed 22, 23,43> Recently hydrosilation reactions have been used effectively by Ringsdorf 255) and Finkelmann 256) for the synthesis of various novel thermoplastic liquid crystalline copolymers where siloxanes have been utilized as flexible spacers. Introduction of flexible siloxanes also improved the processibility of these materials. 

The interest in this type of copolymers is still very strong due to their large volume applications as emulsifiers and stabilizers in many different systems 43,260,261). However, little is known about the structure-property relationships of these systems 262) and the specific interactions of different segments in these copolymers with other components in a particular multicomponent system. Sometimes, minor chemical modifications in the PDMS-PEO copolymer backbone structures can lead to dramatic changes in its properties, e.g. from a foam stabilizer to an antifoam. Therefore, recent studies are usually directed towards the modification of polymer structures and block lengths in order to optimize the overall structure-property-performance characteristics of these systems 262). 

Atmospheric concentrations of methyl parathion following application of the pesticide to tobacco fields were studied by Jackson and Lewis (1978). They found that levels of methyl parathion decreased rapidly following application of either the emulsifiable concentrate or the microencapsulated form. Air concentrations for the emulsifiable concentrate ranged from 7,408 ng/m immediately following application to 13 ng/m 9 days later. The corresponding measurements for the microencapsulated form were 3,783 and 16 ng/m. ... 

Water absorption is the process of taking up and retaining water uniformly throughout the structure of the host, e.g. on the surface of macromolecules, particularly those with a membrane or emulsifier function. Removal in this case is only possible with the application of much energy and results at least in a change of functional properties of the substances under consideration. 

For application of these fluorochemical finishes to textile fabrics, an extremely important factor is their formulation into suitable aqueous emulsions or dispersions. The quality of the formulation has a critical influence on stability during storage and application, as well as the efficacy of treatment and durability [501,502]. In particular, the choice of surfactant(s) for emulsifying or dispersing must ensure good stability with freedom from deposition on rollers, yet must not impair the water and oil repellency of the finished fabric. No individual product fulfils all requirements hence specifically formulated products are available for certain fibre types. 

Individual applications of 0.014-0.019 kg/ha, emulsifiable concentrate, oil diluent, 3 applications at 5-week intervals 0.02 kg/ha, granularformulation, single application 0.025 kg/ha, single application 0.028 kg/ha (0.025 Ibs/acre), single aerial application, mosquito larvicide granules Individual applications of 0.028 kg/ha, 4 applications at 2-week intervals... 

Today, glycerol has over 2000 different applications, in cosmetics, pharmaceutics, foods and drinks, tobacco, paper, inks and printing colors, the production of phthalic and maleic alkyd resins and crosslinked polyesters, and as a hydraulic agent. Polyglycerols have a wide range of applications as emulsifiers, and technical esters of glycerol with fatty acids are used as synthetic lubricants [4]. 

Glucose octadienyl ether (DS = 2) is non-toxic with good skin compatibility [73]. The viscosity of derivative with moderate degree of substitution (DS = 1.5) reaches 2500 cPs at 25°C and potential applications as emulsifiers or defoamers are conceivable. 

Emulsifiable PVA, which produces a film that can be softened with water, restoring adhesiveness and thereby permitting application of a film to a surface long before the subsequent application of a water-based overlay. Its use is limited to specific applications where the possible infiltration of moisture to the bond line is precluded. 

It is worth noting that the effect of temperature on ionic and polyethoxy-lated nonionic surfactants is just opposite. As temperature increases, the nonionics become more lipophilic whereas the ionics turn more hydrophilic. By mixing the two types of surfactants in a proper proportion, these effects could cancel each other out, and the mixture is said to be insensitive to temperature. This interesting feature of ionic-nonionic surfactant mixtures may be considered as a synergy, since it could be very important in practice. Analysis of this feature is not included here, because plenty of information may be found in the literature on applications of such mixtures to equihbrated and emulsified systems [10,71-74]. 

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. All 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 applications. Despite the high concentration of emulsifiers in most synthetic latices, only a small proportion is present in the aqueous phase neady all of it is adsorbed on the polymer particles. 

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