Ester ethoxylates

Ethoxylated Anhydrosorbitol Esters. Ethoxylation of sorbitan fatty acid esters leads to a series of more hydrophilic surfactants (Table 19). All hydroxyl groups of sorbitan can react with ethylene oxide. The stmcture of the principal component of a nominal polyoxyethylene (20) sorbitan monostearate illustrates the composition of these products, where w x y z = 20. 

Natural Ethoxylated Fats, Oils, and Waxes. Castor oil (qv) is a triglyceride high in ticinoleic esters. Ethoxylation in the presence of an alkaline catalyst to a polyoxyethylene content of 60—70 wt % yields water-soluble surfactants (Table 20). Because alkaline catalysts also effect transestenfication, ethoxylated castor oil surfactants are complex mixtures with components resulting from transesterrfication and subsequent ethoxylation at the available hydroxyl groups. The ethoxylates are pale amber Hquids of specific gravity just above 1.0 at room temperature. They are hydrophilic emulsifiers, dispersants, lubricants, and solubilizers used as textile additives and finishing agents, as well as in paper (qv) and leather (qv) manufacture. 

The most common nonionic surfactants are those based on ethylene oxide, referred to as ethoxylated surfactants. Several classes can be distinguished alcohol ethoxylates, alkyl phenol ethoxylates, fatty acid ethoxylates, sorbitan ester ethoxylates, fatty amine ethoxylates, and ethylene oxide-propylene oxide copolymers (sometimes referred to as polymer surfactants). Another important class of nonionics are the multihydroxy products such as glycol esters, glycerol (and polyglycerol) esters, glucosides (and polyglucosides), and sucrose esters. Amine oxides and sulfinyl surfactants represent nonionic with a small head group. 

Nature Fatty Ester Ethoxylate Appearance Paste % Act. 25... 

Fatty ester ethoxylate Fatty esters and emulsifiers blend... 

The chemicals may constitute a substantial portion of the finished textile. In many cases 10% or more of the fabric s final weight may derive from textile chemicals added to improve or enhance one or another of the fabric s properties. Representative raw materials employed for textile finishing applications are fatty alcohol ether sulfates, vinyl acetate-ethylene copolymers, hydrated alumina, alkylolamides, alkoxylates, chlorinated paraffins, alginates, sodium tripolyphosphates, sorbitan fatty acid esters, ethoxylated triglycerides, and silicones. 

Emulsion breakers are typically specific for site or crude-oil type. Conventional emulsion breakers are most commonly formulated from the following types of chemistries polyglycols and polyglycol esters, ethoxylated alcohols and amines, ethoxylated resins, ethoxylated phenol formaldehyde resins, ethoxylated nonylphenols, polyhydric alcohols, and sulfonic acid salts. Commercial emulsion breakers may contain but one type of active ingredient or intermediate or a variety of intermediate types. 

The main nonionic cosofteners are fatty alcohols, fatty acid esters, ethoxylated fatty amines, or lanolin derivatives. To the cationic-anionic systems belong ether sulfates, alkyl sulfonates, or fatty acids [5,6,10]. In all the blends, the weight ratio of DHTDMAC to the cosoftener is always greater than unity [10]. 

The stability of these products is governed not only by their composition but also by mechanical factors. The finished product is shear sensitive. From a formulation standpoint, usual actives do not enable the production of storage-stable concentrated products without incorporating emulsifiers such as fatty esters, ethoxylated fatty amines, or amides, and the viscosity must be further adjusted using inorganic salts. Moreover, the formulation of concentrates requires alcohol-reduced grades... 

ESD are commonly referred to as antistats or antistatic surfactants , and are mostly low molecular weight ethoxylated amines, quaternary ammonium compounds, phosphates (organic) and PEG esters, ethoxylated esters, and others. They are usually applied in quite large quantities (2% or more), either by compounding directly with the plastics and... 

Solubilization of perfume oil in water produces a clear solution without the use of volatile or drying solvents such as ethanol. Generally, fatty alcohol or sorbitan ester ethoxylates are the most suitable surfactants. Isoceteth-20 is a very efficient solubilizer with a branched-chain hydrophobe. It is also available in liquid form, so minimum heat is needed. Two other effective solubilizers are polysorbate 20 and polysorbate 80. Table 8 shows the weight of surfactant needed per gram of fragrance oil [16]. 

Although there hasn t been a great deal of research on the mechanisms involved in the ethoxylation of esters, one mechanism that has been proposed involves transesterification (7). As shown in Figure 13.12, it is the catalyst (in this case, a mixture of calcium and aluminium alkoxides) that first becomes ethoxylated (forms the metal alkoxyethoxylate). After the catalyst picks up a mole of EO, it then transesterifies with the ester to form methyl ester ethoxylate, alkyl ester ethoxylate, and metal-coordinated methoxide. These steps occur continuously until the available EO is exhausted and a distribution of methyl ester ethoxylate homologues (ethoxymers) is obtained. 

Although very little methyl ester ethoxylates are produced at the present time they are included here because of their potential to have a significant impact on the nonionic surfactants market in the future. The general structure of these surfactants (9) is as follows ... 

Methyl ester ethoxylates (MEEs) are a new introduction to the stable of feedstocks which can be ethoxylated, and have only recently become commercially available (currently being produced and utilized in a detergent formulation in Japan by the Lion Corporation). Based on recent literature, however, a significant amount of effort is being focused on the development of MEEs for detergent applications. 

The primary disadvantage of MEEs (or any ester ethoxylates) are that they will hydrolyse at pH levels above about 9. This makes these materials unacceptable for high pH (caustic) cleaners. 

Littau, Ch., Miller, D. 1998. Methyl ester ethoxylates. SOFW-J. 124 690-697. 

Cox, M. F., Weerasooriya, U. 1998. Impact of molecular structure on the performance of methyl ester ethoxylates. J. Surfact. Deterg. 1 11-22. 

Trathnigg, B., Hreczuch, W. 2000. Characterization of fatty ester ethoxylates by coupled chromatographic techniques. Proceedings of the 5th World Surfactant Congress. Firenze, 1 472-480. 

Behler, A., Syldath, A. 2000. Fatty acid methyl ester ethoxylates—a new class of nonionic surfactants. Proceedings of the 5th World Surfactants Congress. Firenze, 1 382-391. 

Fumarate, Tartrate, Succinate Esters Ethoxylated Derivatives... 

The lipophilic sorbitan esters are converted to hydrophilic oil-in-water emulsifiers by reaction with ethylene oxide to produce sorbitan ester ethoxylates commonly called polysorbates. 

Surface-Active Materials. The active defoamer components are necessarily surface active materials, but this ancillary category covers the surfactants that are often incorporated in the formulation for other effects such as emulsification or to enhance dispersion. Emulsifiers are essential in the common oil-in-water emulsion systems, but they are also required where mixtures of active liquid components are used. For example, specialized oil-in-oil emulsifiers are needed in defoamers based on silicone/polyether mixtures, oil-in-water emulsifiers are incorporated in some defoamers even when the final product contains no water. This is to promote emulsification (self-emulsifiable) or dispersion into aqueous foaming systems. These additives increase the speed of foam decay by promoting rapid dispersion of the defoamer throughout the foaming media. Examples of emulsifying agents used in defoamer compositions are fatty acid esters and metallic soaps of fatty acids fatty alcohols and sulfonates, sulfates, and sulfosuccinates sorbi-tan esters ethoxylated products such as ethoxylated octyl or nonylphenols and silicone-polyether copolymers. 

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