Sorbitan ester ethoxylates

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. 

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]. 

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. 

If a sorbitan ester and a sorbitan ester ethoxylate are present as separate components, they can be determined provided the degrees of ethoxylation and esterification are known. 

COMPOSITIONS CONTAINING SORBITAN ESTERS, ETHOXYLATED SORBITAN ESTERS, AND WATER AS POTENTIAL LUBRICATING SUBSTANCES... 

The results presented in this chapter are a continuation of the studies on mixtures of this type of surfactant. This time, however, water was chosen as the lubricant base. In view of the investigation results presented by Pilpel and Rabbani [112], particular attention was paid in this study to the sorbitan-ester/ethoxylated-sorbitan-ester ratio. An attempt was made to find out how to prepare lubricating substances having the desired parameters (characteristics). 

In view of these investigation results, it has been assumed in this chapter that an appropriate sorbitan-ester/ethoxylated-sorbitan-ester composition will also be capable of producing stable adsorbed films at the lubricant/friction-pair material interface. It is predicted that an optimal arrangement of surfactant molecules in the surface phase can result in a very effective reduction in resistance to motion and in wear and seizure prevention. 

The SML/ESMIS mixture with the ratio of 5 5 turned out to be the most effective one in preventing seizure (figs. 18.26-18.29). Based on a test in which friction-couple load was increased linearly, it was found that the lubricant film broke only when the load reached 2500 N. These data confirm earlier assumptions that the selection of an appropriate ratio of a sorbitan ester/ethoxylated sorbitan ester composition is extremely important for the effective protection of friction couples against detrimental friction effects. 

ALKAMULS sorbitan esters and sorbitan ester ethoxylates are used in the personal care, household, industrial and textile Industries as emulsifiers, solubilizers and lubricants. 

Representative antifogging additives are glycerol monooleate, poly-(glycerol ester)s, sorbitan esters, ethoxylated sorbitan esters, nonyl-phenol ethoxylate or ethoxylated alcohols (5). 

Chem. Descrip. Sorbitan ester, ethoxylated tonic Nature Nonionic... 

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. 

Typical commercial ethoxylated sorbitan fatty acid esters are yellow Hquids, except tristearates and the 4- and 5-mol ethylene oxide adducts which are light tan soHds. These adducts, as well as the 20-mol adducts of the triesters, are insoluble but dispersible in water. The monoester 20-mol adducts are water soluble. Ethoxylated sorbitan esters are widely used as emulsifiers, antistatic agents, softeners, fiber lubricants, and solubilizers. In combination with the unethoxylated sorbitan esters or with mono- or diglycetides, these are often used as co-emulsrfiers. The ethoxylated sorbitan esters are produced by beating sorbitan esters with ethylene oxide at 130—170°C in the presence of alkaline catalysts. 

A series of sorbitol-based nonionic surfactants are used ia foods as water-ia-oil emulsifiers and defoamers. They are produced by reaction of fatty acids with sorbitol. During reaction, cycHc dehydration as well as esterification (primary hydroxyl group) occurs so that the hydrophilic portion is not only sorbitol but also its mono- and dianhydride. The product known as sorbitan monostearate [1338-41 -6] for example, is a mixture of partial stearic and palmitic acid esters (sorbitan monopalmitate [26266-57-9]) of sorbitol, 1,5-anhydro-D-glucitol [154-58-8] 1,4-sorbitan [27299-12-3] and isosorbide [652-67-5]. Sorbitan esters, such as the foregoing and also sorbitan monolaurate [1338-39-2] and sorbitan monooleate [1338-43-8], can be further modified by reaction with ethylene oxide to produce ethoxylated sorbitan esters, also nonionic detergents FDA approved for food use. 

The reaction product with monoethanolamine acts as a thickening agent [41,101] and with alcohols as an emollient [40]. Also reaction products with amino acids and oligo- or polypeptides for use in cosmetic formulations are known [43]. Sorbitan esters from ether carboxylates are described as emulsifiers or mild surfactants in cosmetic formulations [39] and alkyl ether carboxylic acid taurides as nonirritant anionic surfactants for cosmetic cleaners in particular [44]. Using unsaturated ether carboxylates it is possible to make viscous formulations based on combinations of unsaturated and saturated ether carboxylates [111]. Highly purified alkyl ether carboxylates based on alcohol ethoxylates with low free alcohol content have also been described [112]. 

Fatty alcohol- (or alkyl-)ethoxylates, CoE, are considered to be better candidates for LLE based on their ability to induce rapid phase separation for Winsor II and III systems. (Winsor III systems consist of excess aqueous and organic phases, and a middle phase containing bicontinuous microemulsions.) However, C,E,-type surfactants alone cannot extract biomolecules, presumably because they have no net negative charge, in contrast to sorbitan esters [24,26,30,31]. But, when combined with an additional anionic surfactant such as AOT or sodium benzene dodecyl sulfonate (SDBS), or affinity surfactant, extraction readily occurs [30,31]. The second surfactant must be present beyond a minimum threshold value so that its interfacial concentration is sufficiently large to be seen by... 

Non-ionic Alkylphenol ethoxylates, long chain alkanol ethoxylates, long chain alkylamine ethoxylates, sorbitan esters and ethoxylates, castor oil ethoxylates, EO/PO copolymers, acrylic copolymers, polysiloxane-polyether copolymers, fluorosilicones... 

Ethoxylated sorbitan ester surfactant mixtures like Tween 20 (cf. Fig. 2.9.38) were often used in biochemical applications. Detergents of this type were analysed by MALDI MS. The aim was to compare the separation results of TLC and RP-LC and to detect impurities within these ethoxylated sorbitan esters [30], Tween 20, the ethoxylated sorbitan carboxylate was ionised resulting in [M + Na]+ and [M + K]+ ions. The Tween 20 isomeric and homologue molecules contained a varying number of ethoxylate units. The number of EO units (-CH2CH2O-) was determined from 18 to 34 resulting in Am/z 44 equally spaced signals [30]. 

A mixture of sorbitan derivatives named Tween 81 specified as ethoxylated sorbitan esters containing oleic acid, was examined by APCI-FIA-MS and —LC—MS in the positive and negative modes. APCI-MS ionisation was supported by the addition of ammonium acetate resulting in equal spaced (Am/z 44) [M + NH4]+ ions which, in parallel, suppressed [M + Na]+ ions. The FIA—MS(+) spectrum contained ions with m/z between 358 and 974 while negative ionisation led to a series of ions from 399 to 971, Am/z 44 equally spaced, too. 

The ethoxylated sorbitan ester Tween 81 was examined by APCI— FIA—MS—MS(+). The compound was ionised by APCI—FIA—MS(+) under addition of ammonium acetate resulting in ions with Am/z 44 equally spaced signals. The APCI—FIA-MS—MS(+) examination of the... 

The use of surfactants in the food industry has been known for centuries. Naturally occurring surfactants such as lecithin from egg yolk or soybean and various proteins from milk are used for the preparation of many food products, such as mayonnaise, salad creams, dressing, and desserts. Polar lipids such as monoglycerides have been introduced as emulsifiers for food products. More recently, synthetic surfactants such as sorbitan esters (Spans) and their ethoxylates (Tweens), sucrose esters, have been used in food emulsions. It should be mentioned that the structures of many food emulsions is complex, and in... 

The addition of ethylene oxide to sorbitan esters raises the HLB of the resultant ester products. Thus, ethoxylation of sorbitan monolaurate with 4 mol of ethylene oxide per mole of ester will raise the HLB value from 8.3 to 13.3. Values for different sorbitan esters are given in Table 5.10. 

Kosteran Kotilen Series Sorbitan esters and ethoxylates... 

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