Polyethoxylated surfactants

Ysambertt, F., Subero, N., Chavez, G., Bravo, B., Bauza, R., Marquez, N. (2005). Molecular weight and EON distribution of industrial polyethoxylated surfactants by high performance size exclusion chromatography. Sep. Sci. Technol. 40(4), 829-843. 

Ahel M, Giger W, Koch M (1994) Behaviour of alkylphenol polyethoxylate surfactants in the aquatic environment - I. Occurrence and transformation in sewage treatment. Water Res 28 1131-1142... 

Fig. 2.9.37. APCI-FIA-MS-MS(+) (CID) product ionmass spectrum of parent ion withm/z 464 (n = 11,x — 6) of industrial blend of fatty acid amido polyethoxylate surfactants (CnH2n+i-C(0)N(H)(CH2-CH2-0)xH x > 1) (inset) fragmentation scheme...

Figure 1.5. Influence of temperature on the interfacial tension between oil and water in the presence of a polyethoxylated surfactant.

Ionic surfactants are sensitive to water hardness whereas polyethoxylated surfactant are not. Hence the mixing of both types often result in formulations that are salt tolerant for applications such as detergency or enhanced oil recovery. 

Marquez N, Bravo B, Ysambertt F, Chavez G, Subero N, Salager JL (2003) Analysis of Polyethoxylated Surfactants in Microemulsion-oil-water Systemas. Part III. Fractionation and Partitioning of Polyethoxylated Alcohol Surfactants. Anal Chim Acta 477 293-303... 

Graciaa A, Anderez JM, Bracho C, Lachaise J, Salager JL, Tolosa L, Ysambertt F (2006) The Selective Partitioning of the Oligomers of Polyethoxylated Surfactant Mixtures between Interface and Oil and Water bulk Phases. Adv Colloid Interface Sci 123-126 63-73... 

There are some similarities between third-phase formation in liquid/liquid extraction and the critical phenomenon of cloud points in aqueous solutions of nonionic polyethoxylated surfactants (12, 91). When a nonionic micellar solution is heated to a certain temperature, it becomes turbid, and by further increasing the temperature,... 

Organic chemicals that are susceptible to oxidation and are of concern from the perspective of contamination and environmental degradation include aliphatic and aromatic hydrocarbons, alcohols, aldehydes, and ketones phenols, polyphenols, and hydroquinones sulfides (thiols) and sulfoxides nitriles, amines, and diamines nitrogen and sulfur heterocyclic compounds mono- and di-halogenated aliphatics linear alkybenzene-sulfonate and nonylphenol polyethoxylate surfactants and thiophosphate esters. Table... 

Ahel, M., C. Schaffner, and W. Giger. 1996. Behaviour of alkylphenol polyethoxylate surfactants in the aquatic environmentlll. Occurrence and elimination of their persistent metabolites during infiltration of river water to groundwater. Water Res. 30 37-46. 

Nonionic polyethoxylated surfactants exemplified by Triton X-405, tend to chain transfer in redox-initiated emulsion polymerizations and become chemically bound to the polymer. 

Figure 8. Inhibition of phenanthrene mineralization in soil-aqueous systems with Tween-type sorbitan polyethoxylate surfactant.

An early indication that a widely used agricultural chemical might be metabolized to a nonpolar conjugate in plants came from an in vitro enzyme study with C-labeled surfactants of the Triton family. A crude particulate enzyme preparation from com shoots catalyzed the formation of fatty acid ester conjugates from the two 1"c-labeled polyethoxylated surfactants indicated below (Equation 32). The ester conjugates were formed primarily from palmitic and linoleic acids 0851). They were identified by mass spectrometry and by GLC analysis of hydrolysis products (J48). In vljro, rice and... 

Giger, W., M.Ahel, M.Koch, H.U.Laubscher, C.Schaffner and J.Schneider. 1987b. Behaviour of alkylphenol polyethoxylate surfactants and of nitrilotriacetate in sewage treatment. Water Sci. Technol. 19 449-460. 

In these expressions, S is the salinity of the aqueous phase (in wt.% NaCl) and In S its neperian logarithm, ACN is the alkane carbon number which characterises the oil phase, cr is a characteristic parameter of the anionic or cationic surfactant which increases linearly with the length of the lipophilic tail, as well as a which is characteristic of the lipophilic group of non-ionic surfactants, EON is the average number of ethylene oxide groups per polyethoxylated surfactant molecule and T is the temperature, k, b, a-x and ct are constants which depend on the kind of system particularly the surfactant head group and electrolyte nature [23-25]. For ethoxylated non-ionics, the characteristic parameter (3 = a - EON is sometimes introduced./(A) and < >(A) are function of the alcohol type and concentration which could be written in first approximation as... 

In ionic surfactant systems, the partition coefficient between excess phases is often found to be unity, hence an optimum formulation is defined by SAD = 0. With polyethoxylated surfactants, the CMC in water is often extremely low, whereas the monomer solubility in many oils is high. Consequently, the assumption of unit activity coefficient is not valid anymore and the partition coefficient between excess phases is not unity. In such cases, the partition coefficient value at optimum formulation is taken as a reference, and the deviation from this reference, the so-called hydrophilic-lipophilic deviation (HLD) is defined by dividing by RT to make the yardstick dimensionless [34]. 

By definition, HLD = 0 at optimum formulation, and away from it, it is the expression of the relative surfactant affinity difference from it. Since the partition coefficient may be measured with a proper analytical technique, its variation with respect to formulation variables such as surfactant EON, oil ACN, water salinity S etc. may be determined. Such studies have been carried extensively with polyethoxylated surfactants and have shown that HLD dependence on the formulation variables has the same expression than the correlation for three-phase behaviour [35, 36]. It holds... 

Graciaa, A., Anderez, J.M., Bracho, C.L., Lachaise, J., Salager, J.L., Tolosa, L. and Ysambertt, F. (2006) The selective partitioning of the oligomers of polyethoxylated surfactant mixtures between interface and oil and water bulk phases. Adv. Colloid Interface ScL, 123-126, 63-73. 

Shang, D. Y., Ikonomou, M. G., and Macdonald, R. W., Quantitative determination of nonylphenol polyethoxylate surfactants in marine sediment using normal-phase liquid chromatography-electrospray mass spectrometry, J. Chromatogr. A, 849, 467-482, 1999. 

S. Horikoshi, N. Watanabe, H. Onishi, H. Hidaka, N. Serpone, Photodecomposition of a nonylphenol polyethoxylate surfactant in a cylindrical photoreactor with Ti02 immobilized fiberglass cloth . Applied Catalysis B Environmental, 37, 117-129, (2002). 

An interesting phenomenon has been observed on reduction of iron. The surfactant chemistry has influenced the iron crystal structure. If the anionic surfactants (such as AOT) are used, we obtain a-Fe with a body-centered (bcc) crystal structure [198]. If the nonylphenol polyethoxylate surfactant is used, the crystals with the face-centered (fee) lattice are formed [199]. Similar data are known for metallic alloys. For this purpose, a mixture of metal salts has been subjected to the joint reduction [200]. It is essential that the reduction happens simultaneously with the formation of multication phases. 

Polyethoxylated surfactants were separated based on the number of ethylene oxide oligomers (EON). Two mefliods were utilized. A silica column (A = 270 nm) and a 30-min 100/0 70/30 (90/5/5 n-heptane/chloroform/methanol)/(50/50 chloro-form/methanol) gradient was able to produce a well-structured profile for EON = 1-25. An aminopropyl colunrn was used for an EON 1-30 polymer. A 45-min 100/0-> 80/20 (90/5/5 n-heptane/chloroform/methanol)/(50/50 chloroform/ metha-nol) gradient gave good profile definition. Samples were made up to a concentration of 0.05 mol/L [640]. 

Halverson, J. D., MaldareUi, C., Couzis, A., and Koplik, J. 2009. Wetting of hydrophobic substrates by nanodroplets of aqueous trisUoxane and alkyl polyethoxylate surfactant solutions. Chem. Eng. Sci. 64 4657. 

This approach may have a number of problems, which are difficult to overcome. Polyethoxylated surfactants are famous for their very low critical micelle concentrations, and thus have outstanding interfacial properties, being extremely efficient solubilizers, detergents and emulsifiers. In a realization of the biphasic technique, these properties may ruin the whole scheme, as the emulsions formed may be very hard to destroy, and solubilization may decrease the recovery of catalyst. 

Figure 8.3. Model relating the foliar uptake of neutral compounds to their log P and the interaction of this variable with the E content of polyethoxylate surfactants applied in combination with the compounds/" ...

Carbonyl content is normally determined for polyethoxylated surfactants, such as EO/PO copolymers, that do not have a carbonyl group as part of their nominal structure. The presence of carbonyl compounds in polyethers indicates that some degradation of the product has taken place, or that lower molecular weight aldehydes were not stripped properly. Oxidation of ethoxylates results in the formation of formaldehyde, formic acid, acetaldehyde, and acetic acid, with the carbonyl functionality of primary interest being the aldehyde group (79,80). There is some interest in formate esters of the type R(OCH2CH2) OCHO, since they can be formed in photoinduced degradation (86,156). 

Rastogi, S. C., Headspace analysis of 1,4-dioxane in products containing polyethoxylated surfactants by GC-MS, Chromatographia, 1990, 29,441—445. 

Crescenzi, C., A. Di Corcia, R. Samperi, A. Marcomini, Nonionic polyethoxylate surfactants in environmental waters by LC/electrospray MS, Anal. Chem., 1995,67,1797-1804. Melander, W. R., A. Nahum, C. Horvath, Changes in conformation and retention of oligo(ethylene glycol) derivatives with temperature and eluent composition, J. Chromatogr., 1979,185, 129-152. 

Ventura, F., A. Figueras, J. Caixach, I. Espadaler, J. Romero, J. Guardiola, J. Rivera, Characterization of polyethoxylated surfactants and their brominated derivatives formed at the water treatment plant of Barcelona by GC-MS and FAB-MS, WaterRes., 1988,22, 1211-1217. 

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