Ethoxylates method

HydrophobicaHy Modified, Ethoxylated Urethane. HEUR associative thickeners are in effect poly(oxyethylene) polymers that contain terminal hydrophobe units (66). They can be synthesized via esterification with monoacids, tosylation reactions, or direct reaction with monoisocyanates. There are problems associated with aH of the methods of synthesis. The general commercial procedure for their synthesis is by a step-growth addition of... 

Alkylamines and diamines are generally classified as corrosive to the skin based on results from laboratory animal (rabbit) studies performed in accordance with the Department of Transportation (DOT) test method (84) rabbits are considered to be especially sensitive to alkylamines which even at low concentrations can induce skin redness and swelling. Oleylamine has been shown to induce mild to moderate skin irritation in laboratory rats when appHed at a concentration of 0.3% in mineral oil (Chemical Manufacturer s Association, 1985). Fatty amines which contain alkyl chains of 10—14 carbons are considered more irritating than related products which contain alkyl chains of 14—18 carbon atoms. Ethoxylation generally decreases the irritation potential of alkylamines. 

The complete analysis of alcohol sulfates is described in the Standard Methods of the International Organization of Standards (ISO) [200] and of the American Society for Testing and Materials (ASTM) [201]. These methods describe the analysis of inorganic sulfate content, chloride content, unsulfated matter, and water as well as other analytical values. Other ISO standards describe the analysis of sodium secondary alkyl sulfates [202], determination of pH [203], determination of water content [204,205], chlorides [206], total active matter in sul fated ethoxylated alcohols and alkylphenols [207], mean relative molecular mass in sulfated ethoxylated alcohols and alkylphenols [208], sulfate content... 

In 1948 Sandoz A.G. found a more simple method of preparation [3-7]. An ethoxylated compound was reacted with a molar amount of NaOH and after that with twice a molar amount of chloroacetic acid. In 1953 a process was patented in which sodium monochloroacetate instead of chloroacetic acid was used [8]. 

There are two important methods for the synthesis of ether carboxylates from ethoxylated fatty alcohols ... 

In comparison with other anionics, little has been published concerning methods of analysis of ether carboxylates. Gerhardt et al. [238] investigated the analytical determination of ether carboxylic acids in reaction mixtures obtained by reaction of nonylphenol ethoxylates with sodium chloroacetate as well as by cyanoethylation by different methods. Several methods, used for other surfactants as well [239], can be used for ether carboxylates. 

Mengerink et al. [243] describe for the analysis of ether carboxylic acids and mixtures thereof with ethoxylated alcohols an HPLC method with the use of a evaporative light-scattering detector (ELSD). 

The amount of residual sulfonate ester remaining after hydrolysis can be determined by a procedure proposed by Martinsson and Nilsson [129], similar to that used to determine total residual saponifiables in neutral oils. Neutrals, including alkanes, alkenes, secondary alcohols, and sultones, as well as the sulfonate esters in the AOS, are isolated by extraction from an aqueous alcoholic solution with petroleum ether. The sulfonate esters are separated from the sultones by chromatography on a silica gel column. Each eluent fraction is subjected to saponification and measured as active matter by MBAS determination measuring the extinction of the trichloromethane solution at 642 nra. (a) Sultones. Connor et al. [130] first reported, in 1975, a very small amount of skin sensitizer, l-unsaturated-l,3-sultone, and 2-chloroalkane-l,3-sultone in the anionic surfactant produced by the sulfation of ethoxylated fatty alcohol. These compounds can also be found in some AOS products consequently, methods of detection are essential. 

A lauryl alcohol ethoxylate therefore will not only contain ethoxylated alcohol with a degree of ethoxylation from 1 to 10 mol of ethylene oxide according to a Poisson contribution but due to currently typical production methods also significant amounts of unreacted fatty alcohol. 

Simple mixtures—like in alkyl sulfosuccinates—can be run using only one solvent. For more complex systems (e.g., ethoxylated fatty alcohol sulfosuccinates) a gradient technique is strongly recommended Technical mixtures of disodium laureth sulfosuccinate could be separated [68]. The separation was so effective that resolution of single homologs of ethoxylates was possible. The detection limit of this method lies at around 0.5 pg. Therefore reverse phase ion pair chromatography seems to be an excellent tool to analyze sulfosuccinates directly without the use of any kind of manipulation. 

In two studies the cleansing and irritancy behavior of surfactants [106,107] were examined. An automated skin brushing method using a specific test soil and an epicutaneous irritation test on the dorsum of volunteers were applied. A sodium sulfosuccinate monoester based on a fatty alcohol ethoxylate gave very favorable results with respect to skin mildness although this concurred with low detergency. 

A great number of nonionic surfactants have been ethoxylated and subsequently reacted with P4O10. The acid phosphate esters from this reaction possess surface properties and detergency similar to the nonionic surface-active agents employed as reactants. Detergency tests and foam heights from the Ross-Miles method have been reported for a series of compounds. Various formulations for all-purpose cleaners are given as well [37,40,41,44,48]. 

For formation of anticorrosive and adhesion-improving protective layers on metals the cleaned surface is treated with aqueous acidic solution containing molybdate, chromium fluoride, phosphate, acetate, and Zn ions. As dispersant a mixture of 60% alkali salt of a phosphate ester, 20% alkylpolyglucoside, and 20% fatty alcohol ethoxylate was applied. This method passivates the metal surface by formation of an anticorrosive and protective layer that improves adhesion of subsequent coatings. 

The phase inversion temperature (PIT) method is helpful when ethoxylated nonionic surfactants are used to obtain an oil-and-water emulsion. Heating the emulsion inverts it to a water-and-oil emulsion at a critical temperature. When the droplet size and interfacial tension reach a minimum, and upon cooling while stirring, it turns to a stable oil-and-water microemulsion form. " ... 

Oil-in-water emulsions provide a cost-effective alternative to the methods mentioned previously, namely, heating or diluting. A typical transport emulsion is composed of 70% crude oil, 30% aqueous phase, and 500 to 2000 ppm of a stabilizing surfactant formulation [1497]. Nonionic surfactants are relatively insensitive to the salt content of the aqueous phase ethoxylated alkylphenols have been used successfully for the formation of stable emulsions that resist inversion. 

Polycarboxylated polyalkoxylates and their sulfate derivatives may be prepared by reacting an ethoxylated or propoxylated alcohol with a water-soluble, alkali or earth alkali metal salt of an unsaturated carboxylic acid [339]. The reaction occurs in aqueous solution in the presence of a free radical initiator and gives products of enhanced yield and reduced impurity levels, compared with the essentially anhydrous reactions with free carboxylic acids, which have been used otherwise. The method provides products that give solutions that are clear on neutralization, remain clear and homogeneous on dilution, and are useful as cleaning agents in drilling and other oil field operations. 

P. R. Hart. Method of breaking water-in-oil emulsions by using quaternary alkyl amine ethoxylates. Patent US 5250174, 1993. 

Some typical areas for SFC comprise waxes, surfactants and dyes. Marked advantages of SFC over GC in the analysis of surfactants (e.g. ethoxylates) have been reported [246]. It is arguably the best chromatographic method for the separation of nonionic surfactants, as reviewed by Cserhati and Forgacs [306]. pSFC-UV-ELSD has been used for separation of oligomers of the nonionic surfactant Triton X-100 [249]. 

FD-MS is also an effective analytical method for direct analysis of many rubber and plastic additives. Lattimer and Welch [113,114] showed that FD-MS gives excellent molecular ion spectra for a variety of polymer additives, including rubber accelerators (dithiocar-bamates, guanidines, benzothiazyl, and thiuram derivatives), antioxidants (hindered phenols, aromatic amines), p-phcnylenediamine-based antiozonants, processing oils and phthalate plasticisers. Alkylphenol ethoxylate surfactants have been characterised by FD-MS [115]. Jack-son et al. [116] analysed some plastic additives (hindered phenol AOs and benzotriazole UVA) by FD-MS. Reaction products of a p-phenylenediaminc antiozonant and d.v-9-lricoscnc (a model olefin) were assessed by FD-MS [117],... 

It is important that any method for surfactant analysis maintains the same oligomer distribution in the extracted samples. LLE and SPE are generally combined with chromatographic methods for separation and resolution of non-ionic surfactants into their ethoxamers. An alternative is the use of SPME-HPLC, recently reported by Chen and Pawliszyn [141]. Alkylphenol ethoxylate surfactants such as Triton X-100 and various Rexol grades in water were determined by means of SPME-NPLC-UV (at 220 nm) [142]. Detection limits for individual alkylphenol ethoxamers were at low ppb level. 

The application range of cSFC-DFI-MS (Table 7.41) appears to be restricted either to the analysis of low-MW substances or to problems related to high-MW samples where low detection limits are not needed [124,444,445], The analysis of surfactants [446] by SFC-MS is frequently performed to demonstrate the feasibility of newly developed interface technology for practical applications. A rugged cSFC-MS method has been developed for the analysis of ethoxylated alcohols (AEs), which are non-ionic surfactants incorporated into a wide variety of industrial and consumer products [447]. cSFC-DFT-DFS was used for the analysis of low-MW, thermally unstable peroxides, and the higher-MW surfactants Triton X-100 and... 

For analysis of surfactants, i.e. detection, identification and quantification, LC-TSP-MS and MS/MS are also qualified methods for substance-specific information [600-602]. A mixture of non-ionic surfactants, comprising nonylphenol ethoxylates [C9Hi9-(CeH4)-0-(CH2-CH2-0)m-H], anionic surfactants and PEG, was... 

When surfactant molecules contain more than one distribution, for example, a distribution of chain lengths in the hydrophobic and hydrophilic portions, two-dimensional liquid chromatography (2DLC) is a very powerful method for complete analysis. One can get the full quantitation of the distribution of molecular size by using the 2DLC technique. For example, take a surfactant molecule like alcohol ethoxylates (AE s) having a general structure of... 

The third method of obviating precipitation of an ionic agent-ionic dye complex is to choose what effectively amounts to a modified ionic agent. Ethoxylated anionic and ethoxylated cationic agents are particularly useful in this respect. The ethoxylation tends to... 

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